diff --git a/backends/postgres/include/postgres_parameter_binder.h b/backends/postgres/include/postgres_parameter_binder.h
index d327559..917295a 100644
--- a/backends/postgres/include/postgres_parameter_binder.h
+++ b/backends/postgres/include/postgres_parameter_binder.h
@@ -31,8 +31,9 @@ public:
   void write_value(size_t pos, const bool &x) override;
   void write_value(size_t pos, const float &x) override;
   void write_value(size_t pos, const double &x) override;
-  void write_value(size_t pos, const time &x ) override;
-  void write_value(size_t pos, const date &x ) override;
+  void write_value(size_t pos, const utils::date_type_t &x ) override;
+  void write_value(size_t pos, const utils::time_type_t &x ) override;
+  void write_value(size_t pos, const utils::timestamp &x ) override;
   void write_value(size_t pos, const char *x) override;
   void write_value(size_t pos, const char *x, size_t size) override;
   void write_value(size_t pos, const std::string &x) override;
diff --git a/backends/postgres/include/postgres_statement.hpp b/backends/postgres/include/postgres_statement.hpp
index 56a1ad9..e882738 100644
--- a/backends/postgres/include/postgres_statement.hpp
+++ b/backends/postgres/include/postgres_statement.hpp
@@ -11,7 +11,8 @@ namespace matador::backends::postgres {
 class postgres_statement final : public sql::statement_impl
 {
 public:
-  postgres_statement(PGconn *db, std::string name, const sql::query_context &query);
+  postgres_statement(PGconn *db, PGresult *res, std::string name, const sql::query_context &query);
+  ~postgres_statement() override;
 
   utils::result<size_t, utils::error> execute(const sql::parameter_binder& bindings) override;
   utils::result<std::unique_ptr<sql::query_result_impl>, utils::error> fetch(const sql::parameter_binder& bindings) override;
@@ -21,6 +22,7 @@ protected:
 
 private:
   PGconn *db_{nullptr};
+  PGresult *res_ = nullptr;
 
   std::string name_;
 };
diff --git a/backends/postgres/src/postgres_connection.cpp b/backends/postgres/src/postgres_connection.cpp
index 575f6e4..4f31837 100644
--- a/backends/postgres/src/postgres_connection.cpp
+++ b/backends/postgres/src/postgres_connection.cpp
@@ -86,15 +86,18 @@ utils::result<std::unique_ptr<sql::query_result_impl>, utils::error> postgres_co
   PGresult *res = PQexec(conn_, context.sql.c_str());
 
   if (is_result_error(res)) {
-    return utils::failure(make_error(sql::error_code::FETCH_FAILED, res, conn_, "Failed to fetch", context.sql));
+    const auto err = make_error(sql::error_code::FETCH_FAILED, res, conn_, "Failed to fetch", context.sql);
+    PQclear(res);
+    return utils::failure(err);
   }
 
   std::vector<object::attribute> prototype = context.prototype;
 
   const int num_col = PQnfields(res);
   if (prototype.size() != static_cast<size_t>(num_col)) {
-    return utils::failure(make_error(sql::error_code::FETCH_FAILED, res, conn_,
-                                     "Number of received columns doesn't match expected columns.", context.sql));
+    const auto err = make_error(sql::error_code::FETCH_FAILED, res, conn_, "Number of received columns doesn't match expected columns.", context.sql);
+    PQclear(res);
+    return utils::failure(err);
   }
   for (int i = 0; i < num_col; ++i) {
     if (!prototype.at(i).is_null()) {
@@ -127,13 +130,13 @@ utils::result<std::unique_ptr<sql::statement_impl>, utils::error> postgres_conne
   const sql::query_context &context) {
   auto statement_name = generate_statement_name(context);
 
-  const PGresult *result = PQprepare(conn_, statement_name.c_str(), context.sql.c_str(), static_cast<int>(context.bind_vars.size()), nullptr);
+  PGresult *result = PQprepare(conn_, statement_name.c_str(), context.sql.c_str(), static_cast<int>(context.bind_vars.size()), nullptr);
 
   if (is_result_error(result)) {
     return utils::failure(make_error(sql::error_code::PREPARE_FAILED, result, conn_, "Failed to prepare", context.sql));
   }
 
-  std::unique_ptr<sql::statement_impl> s(std::make_unique<postgres_statement>(conn_, statement_name, context));
+  std::unique_ptr<sql::statement_impl> s(std::make_unique<postgres_statement>(conn_, result, statement_name, context));
   return utils::ok(std::move(s));
 }
 
@@ -277,8 +280,11 @@ utils::result<bool, utils::error> postgres_connection::exists(const std::string
 
   const auto result = utils::to<size_t>(PQcmdTuples(res));
   if (!result) {
+    PQclear(res);
     return utils::failure(make_error(sql::error_code::FAILURE, res, conn_, "Failed to convert result value", stmt));
   }
+
+  PQclear(res);
   return utils::ok(*result == 1);
 }
 
diff --git a/backends/postgres/src/postgres_parameter_binder.cpp b/backends/postgres/src/postgres_parameter_binder.cpp
index 561f258..5bb4083 100644
--- a/backends/postgres/src/postgres_parameter_binder.cpp
+++ b/backends/postgres/src/postgres_parameter_binder.cpp
@@ -47,15 +47,15 @@ void bind_value(postgres_parameter_binder::bind_data &data, const size_t index,
 
 postgres_parameter_binder::bind_data::bind_data(const size_t size)
 : strings(size)
-, bytes(size)
-, values(size)
-, lengths(size)
-, formats(size)
-{}
+  , bytes(size)
+  , values(size)
+  , lengths(size)
+  , formats(size) {
+}
 
 postgres_parameter_binder::postgres_parameter_binder(const size_t size)
-: bind_data_(size)
-{}
+: bind_data_(size) {
+}
 
 void postgres_parameter_binder::write_value(const size_t pos, const int8_t &x) {
   detail::bind_value(bind_data_, pos, x);
@@ -123,31 +123,34 @@ void postgres_parameter_binder::write_value(const size_t pos, const std::string
   write_value(pos, x);
 }
 
-void postgres_parameter_binder::write_value(const size_t pos, const time &/*x*/) {
-    // bind_data_.strings[pos] = utils::to_string(x, "%Y-%m-%d %T.%f");
-    bind_data_.values[pos] = bind_data_.strings[pos].data();
-    bind_data_.lengths[pos] = static_cast<int>(bind_data_.strings[pos].size());
-    bind_data_.formats[pos] = 0;
+void postgres_parameter_binder::write_value(const size_t pos, const utils::date_type_t &/*x*/) {
+  // bind_data_.strings[pos] = utils::to_string(x, utils::date_format::ISO8601);
+  bind_data_.values[pos] = bind_data_.strings[pos].data();
+  bind_data_.lengths[pos] = static_cast<int>(bind_data_.strings[pos].size());
+  bind_data_.formats[pos] = 0;
 }
 
-void postgres_parameter_binder::write_value(const size_t pos, const date &/*x*/) {
-    // bind_data_.strings[pos] = utils::to_string(x, utils::date_format::ISO8601);
-    bind_data_.values[pos] = bind_data_.strings[pos].data();
-    bind_data_.lengths[pos] = static_cast<int>(bind_data_.strings[pos].size());
-    bind_data_.formats[pos] = 0;
+void postgres_parameter_binder::write_value(const size_t pos, const utils::time_type_t &/*x*/) {
+  // bind_data_.strings[pos] = utils::to_string(x, "%Y-%m-%d %T.%f");
+  bind_data_.values[pos] = bind_data_.strings[pos].data();
+  bind_data_.lengths[pos] = static_cast<int>(bind_data_.strings[pos].size());
+  bind_data_.formats[pos] = 0;
+}
+
+void postgres_parameter_binder::write_value(size_t pos, const utils::timestamp &x) {
 }
 
 void postgres_parameter_binder::write_value(const size_t pos, const utils::blob &x) {
   bind_data_.bytes[pos] = x;
-  bind_data_.values[pos] = reinterpret_cast<char*>(bind_data_.bytes[pos].data());
+  bind_data_.values[pos] = reinterpret_cast<char *>(bind_data_.bytes[pos].data());
   bind_data_.lengths[pos] = static_cast<int>(bind_data_.bytes[pos].size());
   bind_data_.formats[pos] = 1;
 }
 
-void postgres_parameter_binder::write_value(const size_t /*pos*/, const utils::value &/*x*/, size_t /*size*/) {}
+void postgres_parameter_binder::write_value(const size_t /*pos*/, const utils::value &/*x*/, size_t /*size*/) {
+}
 
 const postgres_parameter_binder::bind_data &postgres_parameter_binder::params() const {
   return bind_data_;
 }
-
 }
diff --git a/backends/postgres/src/postgres_result_reader.cpp b/backends/postgres/src/postgres_result_reader.cpp
index 33c8bc3..e390e54 100644
--- a/backends/postgres/src/postgres_result_reader.cpp
+++ b/backends/postgres/src/postgres_result_reader.cpp
@@ -153,6 +153,8 @@ void postgres_result_reader::read_value( const char* /*id*/, const size_t index,
   unsigned char* unescaped = PQunescapeBytea(data, &length);
 
   value.assign(unescaped, unescaped+length);
+
+  PQfreemem(unescaped);
 }
 
 template <typename Type>
@@ -168,6 +170,8 @@ void set_value<utils::blob>(const char* str, utils::value& value) {
   unsigned char* unescaped = PQunescapeBytea(reinterpret_cast<const unsigned char*>(str), &length);
 
   value = utils::blob(unescaped, unescaped+length);
+
+  PQfreemem(unescaped);
 }
 
 void postgres_result_reader::read_value(const char * /*id*/, const size_t index, utils::value &val, size_t) {
diff --git a/backends/postgres/src/postgres_statement.cpp b/backends/postgres/src/postgres_statement.cpp
index ef5e8d5..6a49cdb 100644
--- a/backends/postgres/src/postgres_statement.cpp
+++ b/backends/postgres/src/postgres_statement.cpp
@@ -5,12 +5,17 @@
 
 namespace matador::backends::postgres {
 
-postgres_statement::postgres_statement(PGconn *db, std::string name, const sql::query_context &query)
+postgres_statement::postgres_statement(PGconn *db, PGresult *res, std::string name, const sql::query_context &query)
 : statement_impl(query, 0)
 , db_(db)
+, res_(res)
 , name_(std::move(name))
 {}
 
+postgres_statement::~postgres_statement() {
+  PQclear(res_);
+}
+
 utils::result<size_t, utils::error> postgres_statement::execute(const sql::parameter_binder& bindings) {
   const auto* postgres_bindings = dynamic_cast<const postgres_parameter_binder*>(&bindings);
   if (!postgres_bindings) {
@@ -28,12 +33,14 @@ utils::result<size_t, utils::error> postgres_statement::execute(const sql::param
     return utils::failure(make_error(sql::error_code::EXECUTE_FAILED, res, db_, "Failed to execute statement", query_.sql));
   }
 
-  const auto *tuples = PQcmdTuples(res);
-  if (strlen(tuples) == 0) {
-    return utils::ok(static_cast<size_t>(0));
+  size_t value{0};
+  if (const auto *tuples = PQcmdTuples(res); strlen(tuples) != 0) {
+    value = std::stoul(tuples);
   }
 
-  return utils::ok(static_cast<size_t>(std::stoul(tuples)));
+  PQclear(res);
+
+  return utils::ok(value);
 }
 
 utils::result<std::unique_ptr<sql::query_result_impl>, utils::error> postgres_statement::fetch(const sql::parameter_binder& bindings) {
diff --git a/include/matador/object/attribute.hpp b/include/matador/object/attribute.hpp
index 25b7b3b..e504fca 100644
--- a/include/matador/object/attribute.hpp
+++ b/include/matador/object/attribute.hpp
@@ -67,7 +67,7 @@ private:
   friend class object_generator;
 
   std::string name_;
-  std::shared_ptr<object> owner_;
+  std::weak_ptr<object> owner_;
   utils::basic_type type_{utils::basic_type::Null};
   utils::field_attributes options_{};
   null_option_type null_option_{null_option_type::NotNull};
diff --git a/include/matador/object/basic_object_info.hpp b/include/matador/object/basic_object_info.hpp
index 1e63077..111d922 100644
--- a/include/matador/object/basic_object_info.hpp
+++ b/include/matador/object/basic_object_info.hpp
@@ -58,11 +58,11 @@ public:
   [[nodiscard]] bool endpoints_empty() const;
 
 protected:
-  basic_object_info(std::shared_ptr<repository_node> node, std::shared_ptr<class object> &&obj);
+  basic_object_info(const repository_node& node, const std::shared_ptr<class object> &obj);
 
 protected:
   std::shared_ptr<class object> object_;
-  std::shared_ptr<repository_node> node_;            /**< prototype node of the represented object type */
+  const repository_node& node_;            /**< prototype node of the represented object type */
   t_endpoint_map relation_endpoints_;
 };
 
diff --git a/include/matador/object/basic_repository.hpp b/include/matador/object/basic_repository.hpp
new file mode 100644
index 0000000..8a743f4
--- /dev/null
+++ b/include/matador/object/basic_repository.hpp
@@ -0,0 +1,156 @@
+#ifndef MATADOR_BASIC_REPOSITORY_HPP
+#define MATADOR_BASIC_REPOSITORY_HPP
+
+#include "matador/object/error_code.hpp"
+#include "matador/object/object_info.hpp"
+#include "matador/object/repository_node_iterator.hpp"
+
+#include "matador/logger/logger.hpp"
+
+#include "matador/utils/error.hpp"
+#include "matador/utils/result.hpp"
+
+#include <typeindex>
+#include <unordered_map>
+
+namespace matador::object {
+utils::error make_error(error_code ec, const std::string &msg);
+
+class repository_node;
+class const_repository_node_iterator;
+
+class basic_repository {
+public:
+  typedef const_repository_node_iterator const_iterator; /**< Shortcut for the list const iterator. */
+
+  explicit basic_repository(std::string name = "");
+  ~basic_repository();
+
+  /**
+   *
+   * @param node Node to attach
+   * @param parent Name of parent node
+   * @return Attached node
+   */
+  [[nodiscard]] utils::result<repository_node*, utils::error> attach_node(repository_node *node, const std::string &parent);
+
+  /**
+   * Detaches a given node from the schema. If the
+   * node is a parent of other nodes, these nodes  are
+   * detached as well.
+   *
+   * @param node Node to detach from schema
+   * @return Result object indicating success or failure
+   */
+  [[nodiscard]] utils::result<void, utils::error> detach(repository_node *node);
+
+  /**
+   * Return the first schema node.
+   *
+   * @return The first schema node iterator.
+   */
+  [[nodiscard]] const_iterator begin() const;
+
+  /**
+   * Return the last schema node.
+   *
+   * @return The last schema node iterator.
+   */
+  [[nodiscard]] const_iterator end() const;
+
+  /**
+   * Returns true if the schema contains
+   * no schema nodes.
+   *
+   * @return True if the schema is empty
+   */
+  [[nodiscard]] bool empty() const;
+
+  /**
+   * Returns the current number of the schema node.
+   *
+   * @return Number of schema nodes
+   */
+  [[nodiscard]] size_t size() const;
+
+  /**
+   * Returns the name of the schema.
+   *
+   * @return The name of the schema
+   */
+  [[nodiscard]] std::string name() const;
+
+  [[nodiscard]] bool contains(const std::string &name) const;
+  [[nodiscard]] bool contains(const std::type_index &index) const;
+  template < typename Type >
+  [[nodiscard]] bool contains() const {
+    return contains(std::type_index(typeid(Type)));
+  }
+
+
+  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info(const std::type_index& ti) const;
+  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info(const std::string &name) const;
+  template<typename Type>
+  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info() const {
+    return basic_info(std::type_index(typeid(Type)));
+  }
+
+  [[nodiscard]] utils::result<attribute*, utils::error> primary_key_attribute(const std::type_index &ti) const;
+
+  void dump(std::ostream &os) const;
+  static void dump(std::ostream &os, const repository_node& node);
+
+protected:
+  using t_node_map = std::unordered_map<std::string, repository_node*>;
+  using t_type_index_node_map = std::unordered_map<std::type_index, repository_node*>;
+
+protected:
+  [[nodiscard]] const_iterator find_node(const std::string &name) const;
+  [[nodiscard]] const_iterator find_node(const std::type_index &type_index) const;
+  template<typename Type>
+  [[nodiscard]] const_iterator find_node() const {
+    return find_node(std::type_index(typeid(Type)));
+  }
+
+  [[nodiscard]] bool has_node(const std::string &name) const;
+  [[nodiscard]] bool has_node(const std::type_index &index) const;
+  [[nodiscard]] bool has_node(const repository_node* node) const;
+
+  static void insert_node(repository_node *parent, repository_node *child);
+  void remove_node(repository_node *node);
+
+  [[nodiscard]] bool expecting_relation_node(const std::string &name) const;
+  void expect_relation_node(const std::string &name, const std::type_index &ti);
+  void remove_expected_relation_node(const std::string &name);
+
+  [[nodiscard]] std::shared_ptr<object> provide_object_in_advance(const std::type_index &ti, const std::shared_ptr<object>& obj);
+  [[nodiscard]] bool has_object_for_type(const std::type_index &ti) const;
+  [[nodiscard]] std::shared_ptr<object> object_for_type(const std::type_index &ti) const;
+  void remove_object_for_type(const std::type_index &ti);
+
+  [[nodiscard]] bool is_node_announced(const std::type_index &ti) const;
+  void push_announce_node(const std::type_index &ti, std::unique_ptr<repository_node> &&node);
+  [[nodiscard]] repository_node* announce_node(const std::type_index &ti) const;
+  [[nodiscard]] std::unique_ptr<repository_node> pop_announce_node(const std::type_index &ti);
+
+protected:
+  friend class object_generator;
+  template < typename NodeType, template<typename> typename ...Observers >
+  friend class foreign_node_completer;
+  template < typename NodeType, template<typename> typename ...Observers >
+  friend class relation_completer;
+
+  std::string name_;
+  repository_node* root_{nullptr};
+
+  t_node_map nodes_by_name_;
+  t_type_index_node_map nodes_by_type_;
+  logger::logger log_;
+
+  std::unordered_map<std::type_index, std::unique_ptr<repository_node>> announced_node_;
+  std::unordered_map<std::type_index, attribute*> missing_references_{};
+  std::unordered_map<std::string, std::type_index> expected_relation_nodes_;
+  std::unordered_map<std::type_index, std::shared_ptr<object>> object_by_type_{};
+};
+}
+#endif //MATADOR_BASIC_REPOSITORY_HPP
\ No newline at end of file
diff --git a/include/matador/object/foreign_node_completer.hpp b/include/matador/object/foreign_node_completer.hpp
index 01e8ff2..9a2f488 100644
--- a/include/matador/object/foreign_node_completer.hpp
+++ b/include/matador/object/foreign_node_completer.hpp
@@ -1,9 +1,8 @@
 #ifndef FOREIGN_NODE_COMPLETER_HPP
 #define FOREIGN_NODE_COMPLETER_HPP
 
-#include "matador/object/internal/shadow_repository.hpp"
+#include "matador/object/basic_repository.hpp"
 #include "matador/object/internal/observer_list_copy_creator.hpp"
-#include "matador/object/many_to_many_relation.hpp"
 #include "matador/object/repository_node.hpp"
 #include "matador/object/join_columns_collector.hpp"
 #include "matador/object/object_ptr.hpp"
@@ -32,13 +31,9 @@ public:
  */
 template<typename NodeType, template<typename> typename ...Observers>
 class foreign_node_completer final {
-private:
-  using node_ptr = std::shared_ptr<repository_node>;
-
 public:
-  static void complete(const std::shared_ptr<repository_node> &node, const std::vector<std::unique_ptr<observer<NodeType>>> &observers) {
-    internal::shadow_repository shadow(node->repo_);
-    foreign_node_completer completer(shadow, observers);
+  static void complete(repository_node *node, const std::vector<std::unique_ptr<observer<NodeType>>> &observers) {
+    foreign_node_completer completer(node->repo_, observers);
 
     completer.complete_node(node);
   }
@@ -78,12 +73,12 @@ public:
   static void on_has_many_to_many(const char * /*id*/, CollectionType &/*collection*/, const utils::foreign_attributes &/*attr*/) {}
 
 private:
-  explicit foreign_node_completer(internal::shadow_repository &shadow, const std::vector<std::unique_ptr<observer<NodeType>>> &observers)
-  : repo_(shadow)
+  explicit foreign_node_completer(basic_repository &repo, const std::vector<std::unique_ptr<observer<NodeType>>> &observers)
+  : repo_(repo)
   , log_(logger::create_logger("node_completer"))
   , observers_(observers) {}
 
-  void complete_node(const std::shared_ptr<repository_node> &node) {
+  void complete_node(repository_node *node) {
     nodes_.push(node);
 
     NodeType obj;
@@ -102,8 +97,8 @@ private:
     if (repo_.is_node_announced(typeid(Type))) {
       return;
     }
-    const auto node = repository_node::make_node<Type>(repo_.repo(), "", []{ return std::make_unique<Type>(); }, std::move(observers));
-    repo_.push_announce_node(typeid(Type), node);
+    auto node = repository_node::make_node<Type>(repo_, "", []{ return std::make_unique<Type>(); }, std::move(observers));
+    repo_.push_announce_node(typeid(Type), std::move(node));
     // if (auto result = repo_.attach_node(node)) {
       // foreign_node_completer<Type>::complete(result.value(), {});
     // }
@@ -121,8 +116,8 @@ private:
   friend class foreign_node_completer;
 
 private:
-  std::stack<node_ptr> nodes_;
-  internal::shadow_repository &repo_;
+  std::stack<repository_node*> nodes_;
+  basic_repository &repo_;
   logger::logger log_;
   join_columns_collector join_columns_collector_{};
   const std::vector<std::unique_ptr<observer<NodeType>>>& observers_;
@@ -153,8 +148,8 @@ void foreign_node_completer<NodeType, Observers...>::on_has_many(const char * /*
 template<typename NodeType, template<typename> typename ...Observers>
 void foreign_node_completer<NodeType, Observers...>::register_relation_endpoints(const endpoint_ptr &endpoint,
                                                                    const endpoint_ptr &other_endpoint) {
-  endpoint->node_->info_->register_relation_endpoint(other_endpoint->node_->type_index(), endpoint);
-  other_endpoint->node_->info_->register_relation_endpoint(endpoint->node_->type_index(), other_endpoint);
+  endpoint->node().info_->register_relation_endpoint(other_endpoint->node().type_index(), endpoint);
+  other_endpoint->node().info_->register_relation_endpoint(endpoint->node().type_index(), other_endpoint);
   link_relation_endpoints(endpoint, other_endpoint);
 }
 
diff --git a/include/matador/object/internal/shadow_repository.hpp b/include/matador/object/internal/shadow_repository.hpp
deleted file mode 100644
index aaaa1a2..0000000
--- a/include/matador/object/internal/shadow_repository.hpp
+++ /dev/null
@@ -1,52 +0,0 @@
-#ifndef SHADOW_SCHEMA_HPP
-#define SHADOW_SCHEMA_HPP
-
-#include "matador/object/basic_object_info.hpp"
-
-#include "matador/utils/result.hpp"
-#include "matador/utils/error.hpp"
-
-#include <memory>
-#include <typeindex>
-
-namespace matador::object {
-class repository;
-class repository_node;
-class object;
-}
-
-namespace matador::object::internal {
-class shadow_repository {
-private:
-  using node_ptr = std::shared_ptr<repository_node>;
-
-public:
-  explicit shadow_repository(repository& s);
-
-  [[nodiscard]] repository& repo() const;
-  [[nodiscard]] bool contains(const std::type_index& ti) const;
-  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info(const std::type_index& ti) const;
-  [[nodiscard]] utils::result<node_ptr, utils::error> find_node(const std::type_index &type_index) const;
-  [[nodiscard]] utils::result<node_ptr, utils::error> find_node(const std::string &name) const;
-  [[nodiscard]] utils::result<node_ptr, utils::error> attach_node(const std::shared_ptr<repository_node> &node) const;
-  [[nodiscard]] utils::result<void, utils::error> detach_node(const std::shared_ptr<repository_node> &node) const;
-
-  [[nodiscard]] bool expecting_relation_node(const std::string &name) const;
-  void expect_relation_node(const std::string &name, const std::type_index &ti) const;
-  void remove_expected_relation_node(const std::string &name) const;
-
-  [[nodiscard]] std::shared_ptr<object> provide_object_in_advance(const std::type_index &ti, const std::shared_ptr<object>& obj) const;
-  [[nodiscard]] bool has_object_for_type(const std::type_index &ti) const;
-  [[nodiscard]] std::shared_ptr<object> object_for_type(const std::type_index &ti) const;
-  void remove_object_for_type(const std::type_index &ti) const;
-
-  [[nodiscard]] bool is_node_announced(const std::type_index &ti) const;
-  void push_announce_node(const std::type_index &ti, const node_ptr &node) const;
-  [[nodiscard]] node_ptr announce_node(const std::type_index &ti) const;
-  [[nodiscard]] node_ptr pop_announce_node(const std::type_index &ti) const;
-
-private:
-  repository& repo_;
-};
-}
-#endif //SHADOW_SCHEMA_HPP
diff --git a/include/matador/object/object.hpp b/include/matador/object/object.hpp
index 3106aad..688e9b3 100644
--- a/include/matador/object/object.hpp
+++ b/include/matador/object/object.hpp
@@ -11,8 +11,6 @@
 
 namespace matador::object {
 
-class repository;
-
 class object {
 public:
   explicit object(std::string name);
@@ -23,7 +21,6 @@ public:
   [[nodiscard]] const utils::identifier& primary_key() const;
   [[nodiscard]] bool has_primary_key() const;
 
-  [[nodiscard]] bool empty() const;
   [[nodiscard]] const std::string& name() const;
 
   void update_name(const std::string& name);
diff --git a/include/matador/object/object_generator.hpp b/include/matador/object/object_generator.hpp
index 0693590..a1eb8ed 100644
--- a/include/matador/object/object_generator.hpp
+++ b/include/matador/object/object_generator.hpp
@@ -1,7 +1,7 @@
 #ifndef MATADOR_OBJECT_GENERATOR_HPP
 #define MATADOR_OBJECT_GENERATOR_HPP
 
-#include "matador/object/internal/shadow_repository.hpp"
+#include "matador/object/basic_repository.hpp"
 #include "matador/object/object.hpp"
 
 #include "matador/utils/access.hpp"
@@ -10,8 +10,6 @@
 #include <memory>
 
 namespace matador::object {
-class repository;
-
 class pk_type_determinator {
 private:
     pk_type_determinator() = default;
@@ -51,26 +49,26 @@ private:
 
 class object_generator {
 private:
-    explicit object_generator(const repository& repo, const std::shared_ptr<object> &object);
+    explicit object_generator(basic_repository& repo, const std::shared_ptr<object> &object);
 
 public:
     template < class Type >
-    static std::shared_ptr<object> generate(const repository &repo, const std::string &name) {
+    static std::shared_ptr<object> generate(basic_repository &repo, const std::string &name) {
         return generate(std::make_unique<Type>(), repo, name);
     }
 
     template < class Type >
-    static std::shared_ptr<object> generate(std::unique_ptr<Type>&& t, const repository &repo, const std::string &name) {
-        const internal::shadow_repository shadow_repo(const_cast<repository&>(repo));
+    static std::shared_ptr<object> generate(std::unique_ptr<Type>&& t, basic_repository &repo, const std::string &name) {
         const std::type_index ti(typeid(Type));
-        if (shadow_repo.has_object_for_type(ti)) {
-            auto obj = shadow_repo.object_for_type(ti);
-            shadow_repo.remove_object_for_type(ti);
+        if (repo.has_object_for_type(ti)) {
+            auto obj = repo.object_for_type(ti);
+            repo.remove_object_for_type(ti);
             obj->update_name(name);
             return obj;
         }
 
-        auto obj = shadow_repo.provide_object_in_advance(ti, std::make_shared<object>(name));
+        auto obj = std::make_shared<object>(name);
+        std::ignore = repo.provide_object_in_advance(ti, obj);
         object_generator gen(repo, obj);
         access::process(gen, *t);
         return obj;
@@ -127,9 +125,9 @@ private:
     template<typename Type>
     [[nodiscard]] std::shared_ptr<object> fk_object() const;
 
-    static std::shared_ptr<object> acquire_object(repository &repo, const std::type_index &ti, const std::string& name);
+    static std::shared_ptr<object> acquire_object(basic_repository &repo, const std::type_index &ti, const std::string& name);
 private:
-    const repository &repo_;
+    basic_repository &repo_;
     std::shared_ptr<object> object_;
 };
 
@@ -137,7 +135,6 @@ template<typename ValueType>
 void object_generator::on_primary_key(const char *id, ValueType &x, const utils::primary_key_attribute& attr) {
     auto &ref = emplace_attribute<ValueType>(id, { attr.size(), utils::constraints::PrimaryKey }, null_option_type::NotNull);
     prepare_primary_key(ref, utils::identifier(x));
-    // create_pk_constraint(id);
 }
 
 template<typename Type>
@@ -167,15 +164,14 @@ void object_generator::create_fk_constraint(const std::string& name) const {
 template<typename Type>
 std::shared_ptr<object> object_generator::fk_object() const {
     const auto ti = std::type_index(typeid(Type));
-    const internal::shadow_repository shadow_repo(const_cast<repository &>(repo_));
-    if (const auto result = shadow_repo.basic_info(ti)) {
+    if (const auto result = repo_.basic_info(ti)) {
         return result->get().object();
     }
 
-    if (shadow_repo.has_object_for_type(ti)) {
-        return shadow_repo.object_for_type(ti);
+    if (repo_.has_object_for_type(ti)) {
+        return repo_.object_for_type(ti);
     }
-    const auto obj = shadow_repo.provide_object_in_advance(ti, std::make_shared<object>(""));
+    const auto obj = repo_.provide_object_in_advance(ti, std::make_shared<object>(""));
     object_generator gen(repo_, obj);
     Type t;
     access::process(gen, t);
diff --git a/include/matador/object/object_info.hpp b/include/matador/object/object_info.hpp
index 25157c0..05de5c5 100644
--- a/include/matador/object/object_info.hpp
+++ b/include/matador/object/object_info.hpp
@@ -9,35 +9,20 @@
 namespace matador::object {
 class repository_node;
 
-// template<typename Type>
-// class observer_ptr {
-// public:
-//   explicit observer_ptr(std::unique_ptr<observer<Type>> &&o)
-//   : observer_(std::move(o)) {}
-//
-//   operator bool() const { return observer_ != nullptr; }
-//
-//   observer<Type> *get() const { return observer_.get(); }
-//   observer<Type> &operator*() const { return *observer_; }
-//   observer<Type> *operator->() const { return observer_.get(); }
-//
-// private:
-//   std::unique_ptr<observer<Type>> observer_;
-// };
 template<typename Type>
 class object_info final : public basic_object_info {
 public:
   using create_func = std::function<std::unique_ptr<Type>()>;
 
-  object_info(const std::shared_ptr<repository_node>& node,
-              std::shared_ptr<class object> &&obj,
+  object_info(const repository_node& node,
+              const std::shared_ptr<class object> &obj,
               std::vector<std::unique_ptr<observer<Type>>>&& observers,
               create_func&& creator)
-  : basic_object_info(node, std::move(obj))
+  : basic_object_info(node, obj)
   , creator_(std::move(creator))
   , observers_(std::move(observers)){}
 
-  explicit object_info(const std::shared_ptr<repository_node>& node)
+  explicit object_info(const repository_node& node)
   : basic_object_info(node, {}) {
   }
 
@@ -46,13 +31,13 @@ public:
 
   void on_attach() const override {
     for (auto &observer : observers_) {
-      observer->on_attach(*node_, prototype_);
+      observer->on_attach(node_, prototype_);
     }
   }
 
   void on_detach() const override {
     for (auto &observer : observers_) {
-      observer->on_detach(*node_, prototype_);
+      observer->on_detach(node_, prototype_);
     }
   }
 
diff --git a/include/matador/object/relation_completer.hpp b/include/matador/object/relation_completer.hpp
index 3dae179..1f9a83f 100644
--- a/include/matador/object/relation_completer.hpp
+++ b/include/matador/object/relation_completer.hpp
@@ -1,7 +1,7 @@
 #ifndef RELATION_COMPLETER_HPP
 #define RELATION_COMPLETER_HPP
 
-#include "matador/object/internal/shadow_repository.hpp"
+#include "matador/object/basic_repository.hpp"
 #include "matador/object/foreign_node_completer.hpp"
 #include "matador/object/many_to_many_relation.hpp"
 #include "matador/object/join_columns_collector.hpp"
@@ -94,15 +94,11 @@ private:
  */
 template<typename Type, template<typename> typename... Observers>
 class relation_completer final {
-private:
-    using node_ptr = std::shared_ptr<repository_node>;
-
 public:
   using endpoint_ptr = std::shared_ptr<relation_endpoint>;
 
-  static void complete(const std::shared_ptr<repository_node> &node, const std::vector<std::unique_ptr<observer<Type>>> &observers) {
-    internal::shadow_repository shadow(node->repo_);
-    relation_completer completer(shadow, observers);
+  static void complete(repository_node *node, const std::vector<std::unique_ptr<observer<Type>>> &observers) {
+    relation_completer completer(node->repo_, observers);
 
     completer.complete_node_relations(node);
   }
@@ -131,12 +127,12 @@ public:
   void on_has_many_to_many(const char *id, CollectionType &collection, const utils::foreign_attributes &attr);
 
 private:
-  explicit relation_completer(internal::shadow_repository &shadow, const std::vector<std::unique_ptr<observer<Type>>>& observers)
-  : schema_(shadow)
+  explicit relation_completer(basic_repository &repo, const std::vector<std::unique_ptr<observer<Type>>>& observers)
+  : repo_(repo)
   , log_(logger::create_logger("relation_completer"))
   , observers_(observers) {}
 
-  void complete_node_relations(const std::shared_ptr<repository_node> &node) {
+  void complete_node_relations(repository_node* node) {
       nodes_.push(node);
 
       Type obj;
@@ -152,11 +148,11 @@ private:
   static void link_relation_endpoints(const endpoint_ptr &endpoint,
                                       const endpoint_ptr &other_endpoint);
 
-  node_ptr find_node(const std::type_index &ti) const;
+  [[nodiscard]] repository_node* find_node(const std::type_index &ti) const;
 
 private:
-  std::stack<node_ptr> nodes_;
-  internal::shadow_repository &schema_;
+  std::stack<repository_node*> nodes_;
+  basic_repository &repo_;
   logger::logger log_;
   join_columns_collector join_columns_collector_{};
   const std::vector<std::unique_ptr<observer<Type>>>& observers_;
@@ -183,13 +179,13 @@ void relation_completer<Type, Observers...>::on_has_many(const char *id, Collect
   if (const auto it = foreign_node->info_->find_relation_endpoint(typeid(Type)); it != foreign_node->info().endpoint_end()) {
       // corresponding belongs_to is available and was called (has_many <-> belongs_to)
       // complete the relation
-      const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, foreign_node);
+      const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, *foreign_node);
       nodes_.top()->info_->register_relation_endpoint(typeid(value_type), local_endpoint);
       link_relation_endpoints(local_endpoint, it->second);
   } else if (join_column_finder::has_join_column<value_type>(join_column)) {
       // corresponding belongs_to is available but was not called (has_many <-> belongs_to)
       // prepare the relation
-      const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, foreign_node);
+      const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, *foreign_node);
       nodes_.top()->info_->register_relation_endpoint(typeid(value_type), local_endpoint);
   } else {
     // A relation table is necessary
@@ -198,21 +194,23 @@ void relation_completer<Type, Observers...>::on_has_many(const char *id, Collect
     // belongs-to relation handles this relation, the many-to-many
     // relation is maybe detached.
     log_.debug("node '%s' has has many foreign keys '%s' mapped by '%s'", nodes_.top()->name().c_str(), id, join_column);
-    auto node = repository_node::make_node<relation_value_type>(schema_.repo(), id, [join_column] {
+    auto node = repository_node::make_node<relation_value_type>(repo_, id, [join_column] {
       return std::make_unique<relation_value_type>("id", join_column);
     }, {});
-    const auto result = schema_.attach_node(node);
+    const auto result = repo_.attach_node(node.release(), "");
     if (!result) {
       // Todo: throw internal error
       return;
     }
-    const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, node);
-    const auto foreign_endpoint = std::make_shared<relation_endpoint>("id", relation_type::BelongsTo, nodes_.top());
+
+    auto *attached_node = result.value();
+    const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, *attached_node);
+    const auto foreign_endpoint = std::make_shared<relation_endpoint>("id", relation_type::BelongsTo, *nodes_.top());
     nodes_.top()->info_->register_relation_endpoint(typeid(value_type), local_endpoint);
-    node->info_->register_relation_endpoint(nodes_.top()->type_index(), foreign_endpoint);
+    attached_node->info_->register_relation_endpoint(nodes_.top()->type_index(), foreign_endpoint);
     link_relation_endpoints(local_endpoint, foreign_endpoint);
 
-    const auto foreign_value_endpoint = std::make_shared<relation_endpoint>(join_column, relation_type::BelongsTo, foreign_node);
+    const auto foreign_value_endpoint = std::make_shared<relation_endpoint>(join_column, relation_type::BelongsTo, *foreign_node);
     node->info_->register_relation_endpoint(typeid(value_type), foreign_value_endpoint);
   }
 }
@@ -226,20 +224,21 @@ void relation_completer<Type, Observers...>::on_has_many(const char *id, Collect
   using value_type = typename CollectionType::value_type;
   using relation_value_type = many_to_relation<Type, value_type>;
 
-  auto node = repository_node::make_node<relation_value_type>(schema_.repo(), id, [join_column] {
+  auto node = repository_node::make_node<relation_value_type>(repo_, id, [join_column] {
     return std::make_unique<relation_value_type>(join_column, "value");
   }, {});
-  const auto result = schema_.attach_node(node);
+  const auto result = repo_.attach_node(node.release(), "");
   if (!result) {
     // Todo: throw internal exception
     return;
   }
 
-  const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, node);
-  const auto foreign_endpoint = std::make_shared<relation_endpoint>(join_column, relation_type::BelongsTo, nodes_.top());
+  auto *attached_node = result.value();
+  const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasMany, *attached_node);
+  const auto foreign_endpoint = std::make_shared<relation_endpoint>(join_column, relation_type::BelongsTo, *nodes_.top());
 
   nodes_.top()->info_->register_relation_endpoint(typeid(value_type), local_endpoint);
-  node->info_->register_relation_endpoint(nodes_.top()->type_index(), foreign_endpoint);
+  attached_node->info_->register_relation_endpoint(nodes_.top()->type_index(), foreign_endpoint);
   link_relation_endpoints(local_endpoint, foreign_endpoint);
 }
 
@@ -250,11 +249,11 @@ void relation_completer<Type, Observers...>::on_has_many_to_many(const char *id,
                                                    const char *join_column,
                                                    const char *inverse_join_column,
                                                    const utils::foreign_attributes &/*attr*/) {
-  if (!schema_.expecting_relation_node(id)) {
-    schema_.expect_relation_node(id, typeid(typename CollectionType::value_type::value_type));
+  if (!repo_.expecting_relation_node(id)) {
+    repo_.expect_relation_node(id, typeid(typename CollectionType::value_type::value_type));
   } else {
     attach_relation_node<typename CollectionType::value_type::value_type>(id, join_column, inverse_join_column);
-    schema_.remove_expected_relation_node(id);
+    repo_.remove_expected_relation_node(id);
   }
 }
 
@@ -278,7 +277,7 @@ void relation_completer<Type, Observers...>::on_has_one(const char *id,
                                           ForeignPointerType &/*obj*/,
                                           const utils::foreign_attributes &/*attr*/) {
   using value_type = typename ForeignPointerType::value_type;
-  auto foreign_node = find_node(typeid(value_type));
+  const auto foreign_node = find_node(typeid(value_type));
   if (!foreign_node) {
     // Todo: throw internal error or attach node
     return;
@@ -286,7 +285,7 @@ void relation_completer<Type, Observers...>::on_has_one(const char *id,
 
   auto local_it = nodes_.top()->info().find_relation_endpoint(typeid(value_type));
   if (local_it == nodes_.top()->info().endpoint_end()) {
-    const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasOne, foreign_node);
+    const auto local_endpoint = std::make_shared<relation_endpoint>(id, relation_type::HasOne, *foreign_node);
     local_it = nodes_.top()->info_->register_relation_endpoint(typeid(value_type), local_endpoint);
   }
   if (const auto foreign_it = foreign_node->info().find_relation_endpoint(typeid(Type)); foreign_it != foreign_node->info().endpoint_end()) {
@@ -302,7 +301,7 @@ void relation_completer<Type, Observers...>::on_belongs_to(const char *id,
                                              const utils::foreign_attributes & /*attr*/) {
   using value_type = typename ForeignPointerType::value_type;
   const auto ti = std::type_index(typeid(value_type));
-  auto foreign_node = find_node(typeid(value_type));
+  const auto foreign_node = find_node(typeid(value_type));
   if (!foreign_node) {
     // Todo: throw internal error or attach node
     return;
@@ -313,11 +312,11 @@ void relation_completer<Type, Observers...>::on_belongs_to(const char *id,
   if (const auto it = foreign_node->info_->find_relation_endpoint(nodes_.top()->type_index()); it != foreign_node->info().endpoint_end()) {
     // Found corresponding relation endpoint in the foreign node
     if (it->second->is_has_one()) {
-        const auto endpoint = std::make_shared<relation_endpoint>(id, relation_type::BelongsTo, foreign_node);
+        const auto endpoint = std::make_shared<relation_endpoint>(id, relation_type::BelongsTo, *foreign_node);
         nodes_.top()->info_->register_relation_endpoint(ti, endpoint);
         link_relation_endpoints(endpoint, it->second);
     } else if (it->second->is_has_many()) {
-        const auto endpoint = std::make_shared<relation_endpoint>(id, relation_type::BelongsTo, foreign_node);
+        const auto endpoint = std::make_shared<relation_endpoint>(id, relation_type::BelongsTo, *foreign_node);
         nodes_.top()->info_->register_relation_endpoint(ti, endpoint);
         link_relation_endpoints(endpoint, it->second);
     } else if (it->second->foreign_endpoint()->node().type_index() == typeid(many_to_many_relation<Type, value_type>)) {
@@ -326,16 +325,15 @@ void relation_completer<Type, Observers...>::on_belongs_to(const char *id,
       // "belongs_to"-relation the "many_to_many_relation" can be removed
       // (detach), and the endpoints must be adjusted
       const auto foreign_endpoint = it->second->foreign_endpoint();
-      const auto detach_result = schema_.detach_node(foreign_endpoint->node_);
+      const auto detach_result = repo_.detach(foreign_endpoint->node_);
       foreign_endpoint->node_ = foreign_node;
-      // foreign_endpoint->node_ = nodes_.top();
       nodes_.top()->info_->register_relation_endpoint(nodes_.top()->type_index(), foreign_endpoint);
     } else {
       // check type
     }
   } else {
     // Relation node was not found, create only endpoint.
-    const auto endpoint = std::make_shared<relation_endpoint>(id, relation_type::BelongsTo, foreign_node);
+    const auto endpoint = std::make_shared<relation_endpoint>(id, relation_type::BelongsTo, *foreign_node);
     nodes_.top()->info_->register_relation_endpoint(ti, endpoint);
   }
 }
@@ -343,18 +341,17 @@ void relation_completer<Type, Observers...>::on_belongs_to(const char *id,
 template<typename Type, template<typename> typename... Observers>
 template<typename NodeType>
 void relation_completer<Type, Observers...>::attach_relation_node(const std::string &name, const std::string &join_column, const std::string &inverse_join_column) {
-  using relation_value_type = many_to_many_relation<NodeType, Type>;
+  using relation_value_type = many_to_many_relation<Type, NodeType>;
   using value_type = NodeType;
 
   // Check if the object_ptr type is already inserted in the schema (by id)
-  auto foreign_node = find_node(typeid(value_type));
+  const auto foreign_node = find_node(typeid(value_type));
   if (!foreign_node) {
     // Todo: throw internal error or attach node
     return;
   }
 
-  auto result = schema_.find_node(name);
-  if (result) {
+  if (const auto it = repo_.find_node(name); it != repo_.end()) {
     return;
   }
   // Relation does not exist. Create it.
@@ -364,26 +361,27 @@ void relation_completer<Type, Observers...>::attach_relation_node(const std::str
 
   auto observers = internal::observer_list_copy_creator<Type, relation_value_type, Observers...>::copy_create(observers_);
 
-  auto node = repository_node::make_node<relation_value_type>(schema_.repo(), name, std::move(creator), std::move(observers));
-  result = schema_.attach_node(node);
+  auto node = repository_node::make_node<relation_value_type>(repo_, name, std::move(creator), std::move(observers));
+  auto result = repo_.attach_node(node.release(), "");
   if (!result) {
     // Todo: throw internal error
     return;
   }
 
+  auto *attached_node = result.value();
   foreign_node_completer<relation_value_type>::complete(result.value(), {});
 
-  const auto local_endpoint = std::make_shared<relation_endpoint>(name, relation_type::HasMany, node);
-  const auto join_endpoint = std::make_shared<relation_endpoint>(join_column, relation_type::BelongsTo, nodes_.top());
-  const auto inverse_join_endpoint = std::make_shared<relation_endpoint>(inverse_join_column, relation_type::BelongsTo, foreign_node);
-  const auto foreign_endpoint = std::make_shared<relation_endpoint>(name, relation_type::HasMany, node);
+  const auto local_endpoint = std::make_shared<relation_endpoint>(name, relation_type::HasMany, *attached_node);
+  const auto join_endpoint = std::make_shared<relation_endpoint>(join_column, relation_type::BelongsTo, *nodes_.top());
+  const auto inverse_join_endpoint = std::make_shared<relation_endpoint>(inverse_join_column, relation_type::BelongsTo, *foreign_node);
+  const auto foreign_endpoint = std::make_shared<relation_endpoint>(name, relation_type::HasMany, *attached_node);
   // register relation endpoint in local node
   nodes_.top()->info_->register_relation_endpoint(typeid(value_type), local_endpoint);
   // register relation endpoint in foreign node
   foreign_node->info_->register_relation_endpoint(nodes_.top()->type_index(), foreign_endpoint);
   // register endpoints in relation node
-  node->info_->register_relation_endpoint(nodes_.top()->type_index(), join_endpoint);
-  node->info_->register_relation_endpoint(typeid(value_type), inverse_join_endpoint);
+  attached_node->info_->register_relation_endpoint(nodes_.top()->type_index(), join_endpoint);
+  attached_node->info_->register_relation_endpoint(typeid(value_type), inverse_join_endpoint);
   // link endpoints
   link_relation_endpoints(local_endpoint, join_endpoint);
   link_relation_endpoints(foreign_endpoint, inverse_join_endpoint);
@@ -392,8 +390,8 @@ void relation_completer<Type, Observers...>::attach_relation_node(const std::str
 template<typename Type, template<typename> typename... Observers>
 void relation_completer<Type, Observers...>::register_relation_endpoints(const endpoint_ptr &endpoint,
                                                            const endpoint_ptr &other_endpoint) {
-  endpoint->node_->info_->register_relation_endpoint(other_endpoint->node_->type_index(), endpoint);
-  other_endpoint->node_->info_->register_relation_endpoint(endpoint->node_->type_index(), other_endpoint);
+  endpoint->node().info_->register_relation_endpoint(other_endpoint->node().type_index(), endpoint);
+  other_endpoint->node().info_->register_relation_endpoint(endpoint->node().type_index(), other_endpoint);
   link_relation_endpoints(endpoint, other_endpoint);
 }
 
@@ -404,16 +402,15 @@ void relation_completer<Type, Observers...>::link_relation_endpoints(const endpo
 }
 
 template<typename Type, template <typename> class ... Observers>
-typename relation_completer<Type, Observers...>::node_ptr relation_completer<Type, Observers...>::find_node(const std::type_index &ti) const {
-  node_ptr foreign_node;
-  if (auto result = schema_.find_node(ti); result) {
-    return result.value();
+repository_node* relation_completer<Type, Observers...>::find_node(const std::type_index &ti) const {
+  if (const auto it = repo_.find_node(ti); it != repo_.end()) {
+    return it.get();
   }
 
-  if (!schema_.is_node_announced(ti)) {
-    return {};
+  if (!repo_.is_node_announced(ti)) {
+    return nullptr;
   }
-  return  schema_.announce_node(ti);
+  return repo_.announce_node(ti);
 }
 }
 #endif //RELATION_COMPLETER_HPP
diff --git a/include/matador/object/relation_endpoint.hpp b/include/matador/object/relation_endpoint.hpp
index 328a11f..e77a47a 100644
--- a/include/matador/object/relation_endpoint.hpp
+++ b/include/matador/object/relation_endpoint.hpp
@@ -24,15 +24,13 @@ static const utils::enum_mapper<relation_type> relation_type_enum({
 
 class relation_endpoint {
 public:
-  relation_endpoint(std::string field_name, relation_type type, const std::shared_ptr<repository_node>& node);
+  relation_endpoint(std::string field_name, relation_type type, repository_node& node);
 
   [[nodiscard]] std::string field_name() const;
   [[nodiscard]] relation_type type() const;
   [[nodiscard]] std::string type_name() const;
   [[nodiscard]] const repository_node& node() const;
 
-  [[nodiscard]] std::shared_ptr<repository_node> node_ptr() const;
-
   [[nodiscard]] bool is_has_one() const;
   [[nodiscard]] bool is_has_many() const;
   [[nodiscard]] bool is_belongs_to() const;
@@ -48,8 +46,8 @@ private:
 
   std::string field_name_;
   relation_type type_;
-  std::shared_ptr<repository_node> node_;
-  std::shared_ptr<relation_endpoint> foreign_endpoint_;
+  repository_node *node_{nullptr};
+  std::weak_ptr<relation_endpoint> foreign_endpoint_;
 };
 
 }
diff --git a/include/matador/object/repository.hpp b/include/matador/object/repository.hpp
index 1fcb028..95e3f48 100644
--- a/include/matador/object/repository.hpp
+++ b/include/matador/object/repository.hpp
@@ -1,42 +1,23 @@
-#ifndef SCHEMA_HPP
-#define SCHEMA_HPP
+#ifndef REPOSITORY_HPP
+#define REPOSITORY_HPP
 
-#include "matador/logger/log_manager.hpp"
+#include "matador/object/basic_repository.hpp"
 
-#include "matador/object/error_code.hpp"
 #include "matador/object/foreign_node_completer.hpp"
-#include "matador/object/object_info.hpp"
 #include "matador/object/observer.hpp"
 #include "matador/object/relation_completer.hpp"
-#include "matador/object/repository_node.hpp"
-#include "matador/object/repository_node_iterator.hpp"
 
 #include "matador/utils/result.hpp"
 #include "matador/utils/error.hpp"
 
-#include "matador/logger/logger.hpp"
-
 #include <memory>
 #include <string>
 #include <unordered_set>
 
 namespace matador::object {
-namespace internal {
-class shadow_repository;
-}
-
-utils::error make_error(error_code ec, const std::string &msg);
-
-class repository {
+class repository : public basic_repository {
 public:
-  typedef const_repository_node_iterator const_iterator; /**< Shortcut for the list const iterator. */
-
-  using node_ptr = std::shared_ptr<repository_node>;
-
-  /**
-   * Creates an empty schema
-   */
-  explicit repository(std::string name = "");
+  using basic_repository::basic_repository;
 
   template<typename Type, template<typename> typename... Observers>
   [[nodiscard]] utils::result<void, utils::error> attach(const std::string &name, Observers<Type>&&... observers) {
@@ -46,12 +27,12 @@ public:
   template<typename Type, typename SuperType, template<typename> typename... Observers>
   [[nodiscard]] utils::result<void, utils::error> attach(const std::string &name, Observers<Type>&&... observers) {
     const auto ti = std::type_index(typeid(SuperType));
-    auto result = find_node(ti);
-    if (!result) {
+    const auto it = find_node(ti);
+    if (it == end()) {
       return utils::failure(make_error(error_code::NodeNotFound, "Parent node '" + std::string(ti.name()) + "' not found"));
     }
 
-    return attach_type<Type, Observers...>(name, (*result)->name(), std::forward<Observers<Type>>(observers)...);
+    return attach_type<Type, Observers...>(name, it->name(), std::forward<Observers<Type>>(observers)...);
   }
 
   template<typename Type, template<typename> typename... Observers>
@@ -65,20 +46,22 @@ public:
       obs.reserve(sizeof...(Observers));
       (obs.push_back(std::unique_ptr<observer<Type>>(new Observers<Type>(std::forward<Observers<Type>>(observers)))), ...);
       // if the type was not found
-      std::shared_ptr<repository_node> node;
+      std::unique_ptr<repository_node> node;
       if (is_node_announced(typeid(Type))) {
         node = pop_announce_node(typeid(Type));
         node->update_name(name);
       } else {
         node = repository_node::make_node<Type>(*this, name, []{ return std::make_unique<Type>(); }, std::move(obs));
       }
-      if (auto result = attach_node(node, parent); !result) {
+      auto result = attach_node(node.release(), parent);
+      if (!result) {
           return utils::failure(result.err());
       }
 
-      const auto info = node->template info<Type>();
-      foreign_node_completer<Type, Observers...>::complete(node, info.get().observers());
-      relation_completer<Type, Observers...>::complete(node, info.get().observers());
+      repository_node* attached_node = result.value();
+      const auto info = attached_node->template info<Type>();
+      foreign_node_completer<Type, Observers...>::complete(attached_node, info.get().observers());
+      relation_completer<Type, Observers...>::complete(attached_node, info.get().observers());
     } else if (!has_node(name)) {
       it->second->update_name(name);
       nodes_by_name_[name] = it->second;
@@ -95,142 +78,16 @@ public:
     return utils::ok<void>();
   }
 
-  /**
-   * Detaches a given node from the schema. If the
-   * node is a parent of other nodes, these nodes  are
-   * detached as well.
-   *
-   * @param node Node to detach from schema
-   * @return Result object indicating success or failure
-   */
-  [[nodiscard]] utils::result<void, utils::error> detach(const node_ptr &node);
-
-  /**
-   * Return the first schema node.
-   *
-   * @return The first schema node iterator.
-   */
-  [[nodiscard]] const_iterator begin() const;
-
-  /**
-   * Return the last schema node.
-   *
-   * @return The last schema node iterator.
-   */
-  [[nodiscard]] const_iterator end() const;
-
-  /**
-   * Returns true if the schema contains
-   * no schema nodes.
-   *
-   * @return True if the schema is empty
-   */
-  [[nodiscard]] bool empty() const;
-
-  /**
-   * Returns the current number of the schema node.
-   *
-   * @return Number of schema nodes
-   */
-  [[nodiscard]] size_t size() const;
-
-  /**
-   * Returns the name of the schema.
-   *
-   * @return The name of the schema
-   */
-  [[nodiscard]] std::string name() const;
-
-  [[nodiscard]] bool contains(const std::string &name) const;
-  [[nodiscard]] bool contains(const std::type_index &index) const;
-  template < typename Type >
-  [[nodiscard]] bool contains() const {
-    return contains(std::type_index(typeid(Type)));
-  }
-
-
   template<typename Type>
   [[nodiscard]] utils::result<object_info_ref<Type>, utils::error> info() const {
-    auto result = find_node(std::type_index(typeid(Type)));
-    if (!result) {
-      return utils::failure(result.err());
+    const auto it = find_node(std::type_index(typeid(Type)));
+    if (it == end()) {
+      return utils::failure(make_error(error_code::NodeNotFound, "Parent node '" + std::string(typeid(Type).name()) + "' not found"));
     }
 
-    return utils::ok(result.value()->info<Type>());
+    return utils::ok(it->info<Type>());
   }
-
-  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info(const std::type_index& ti) const;
-
-  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info(const std::string &name) const;
-
-  template<typename Type>
-  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info() const {
-    auto result = find_node(std::type_index(typeid(Type)));
-    if (!result) {
-      return utils::failure(result.err());
-    }
-
-    return utils::ok(basic_object_info_ref{result.value()->info()});
-  }
-
-  [[nodiscard]] utils::result<attribute*, utils::error> primary_key_attribute(const std::type_index &type_index) const;
-
-  void dump(std::ostream &os) const;
-  static void dump(std::ostream &os, const node_ptr& node);
-
-private:
-  using t_node_map = std::unordered_map<std::string, node_ptr>;
-  using t_type_index_node_map = std::unordered_map<std::type_index, node_ptr>;
-
-  [[nodiscard]] utils::result<node_ptr, utils::error> attach_node(const node_ptr &node, const std::string &parent);
-  [[nodiscard]] utils::result<node_ptr, utils::error> find_node(const std::string &name) const;
-  [[nodiscard]] utils::result<node_ptr, utils::error> find_node(const std::type_index &type_index) const;
-  template<typename Type>
-  [[nodiscard]] utils::result<node_ptr, utils::error> find_node() const {
-    return find_node(std::type_index(typeid(Type)));
-  }
-
-  [[nodiscard]] bool has_node(const std::string &name) const;
-  [[nodiscard]] bool has_node(const std::type_index &index) const;
-  [[nodiscard]] bool has_node(const node_ptr& node) const;
-
-  static void insert_node(const node_ptr &parent, const node_ptr &child);
-  void remove_node(const node_ptr &node);
-
-  [[nodiscard]] bool expecting_relation_node(const std::string &name) const;
-  void expect_relation_node(const std::string &name, const std::type_index &ti);
-  void remove_expected_relation_node(const std::string &name);
-
-  [[nodiscard]] std::shared_ptr<object> provide_object_in_advance(const std::type_index &ti, const std::shared_ptr<object>& obj);
-  [[nodiscard]] bool has_object_for_type(const std::type_index &ti) const;
-  [[nodiscard]] std::shared_ptr<object> object_for_type(const std::type_index &ti) const;
-  void remove_object_for_type(const std::type_index &ti);
-
-  [[nodiscard]] bool is_node_announced(const std::type_index &ti) const;
-  void push_announce_node(const std::type_index &ti, const node_ptr &node);
-  [[nodiscard]] node_ptr announce_node(const std::type_index &ti);
-  [[nodiscard]] node_ptr pop_announce_node(const std::type_index &ti);
-
-private:
-  friend class internal::shadow_repository;
-  friend class repository_node;
-  template < typename NodeType, template<typename> typename ...Observers >
-  friend class foreign_node_completer;
-  friend class object_generator;
-
-  std::string name_;
-  std::shared_ptr<repository_node> root_;
-
-  t_node_map nodes_by_name_;
-  t_type_index_node_map nodes_by_type_;
-  logger::logger log_;
-
-  std::unordered_map<std::type_index, std::shared_ptr<repository_node>> announced_node_;
-  std::unordered_map<std::type_index, attribute*> missing_references_;
-  std::unordered_map<std::string, std::type_index> expected_relation_nodes_;
-  std::unordered_map<std::type_index, std::shared_ptr<object>> object_by_type_;
-
 };
 }
 
-#endif //SCHEMA_HPP
+#endif //REPOSITORY_HPP
diff --git a/include/matador/object/repository_node.hpp b/include/matador/object/repository_node.hpp
index 0d1f266..91c12e7 100644
--- a/include/matador/object/repository_node.hpp
+++ b/include/matador/object/repository_node.hpp
@@ -1,34 +1,30 @@
-#ifndef SCHEMA_NODE_HPP
-#define SCHEMA_NODE_HPP
+#ifndef REPOSITORY_NODE_HPP
+#define REPOSITORY_NODE_HPP
 
 #include "matador/object/object_generator.hpp"
 #include "matador/object/object_info.hpp"
 #include "matador/object/internal/observer_list_creator.hpp"
 
-#include "matador/utils/error.hpp"
-#include "matador/utils/result.hpp"
-
 #include <memory>
 
 namespace matador::object {
 
 class basic_object_info;
-class repository;
+class basic_repository;
 
 class repository_node final {
 public:
-  using node_ptr = std::shared_ptr<repository_node>;
+  using node_ptr = repository_node*;
   template< typename Type>
   using creator_func = std::function<std::unique_ptr<Type>()>;
 
   template < typename Type, template<typename> typename... Observers >
-  static std::shared_ptr<repository_node> make_node(repository& repo,
+  static std::unique_ptr<repository_node> make_node(basic_repository& repo,
                                                     const std::string& name,
                                                     creator_func<Type> creator,
                                                     std::vector<std::unique_ptr<observer<Type>>>&& observers);
 
-  static std::shared_ptr<repository_node> make_null_node(repository& repo);
-
+  explicit repository_node(basic_repository& repo);
   repository_node(const repository_node& other) = delete;
   repository_node(repository_node&& other) = default;
   repository_node& operator=(const repository_node& other) = delete;
@@ -50,7 +46,7 @@ public:
       return std::ref(static_cast<const object_info<Type>&>(*info_));
   }
 
-  [[nodiscard]] const repository& schema() const;
+  [[nodiscard]] const basic_repository& schema() const;
 
   [[nodiscard]] bool has_children() const;
 
@@ -58,52 +54,52 @@ public:
   void on_detach() const;
 
 private:
-  explicit repository_node(repository& repo);
-  repository_node(repository& repo, const std::type_index& ti);
-  repository_node(repository& repo, std::string name, const std::type_index& ti);
+  repository_node(basic_repository& repo, const std::type_index& ti);
+  repository_node(basic_repository& repo, std::string name, const std::type_index& ti);
 
   void unlink();
 
 private:
-  friend class repository;
+  friend class basic_repository;
   template<typename Type, template<typename> typename... Observers>
   friend class relation_completer;
   template < typename NodeType, template<typename> typename ...Observers >
   friend class foreign_node_completer;
   friend class const_repository_node_iterator;
 
-  repository &repo_;
+  basic_repository &repo_;
   std::type_index type_index_;
   std::unique_ptr<basic_object_info> info_;
 
-  std::shared_ptr<repository_node> parent_;
-  std::shared_ptr<repository_node> previous_sibling_;
-  std::shared_ptr<repository_node> next_sibling_;
-  std::shared_ptr<repository_node> first_child_;
-  std::shared_ptr<repository_node> last_child_;
+  repository_node* parent_{nullptr};
+  repository_node* previous_sibling_{nullptr};
+  repository_node* next_sibling_{nullptr};
+  std::unique_ptr<repository_node> first_child_;
+  std::unique_ptr<repository_node> last_child_;
 
   std::string name_;
   size_t depth_{0};
 };
 
 template<typename Type, template <typename> class ... Observers>
-std::shared_ptr<repository_node> repository_node::make_node(repository &repo, const std::string &name,
-  creator_func<Type> creator, std::vector<std::unique_ptr<observer<Type>>> &&observers) {
+std::unique_ptr<repository_node> repository_node::make_node(basic_repository &repo,
+                                                            const std::string &name,
+                                                            creator_func<Type> creator,
+                                                            std::vector<std::unique_ptr<observer<Type>>> &&observers) {
   const std::type_index ti(typeid(Type));
-  auto node = std::shared_ptr<repository_node>(new repository_node(repo, name, ti));
+  auto node = std::unique_ptr<repository_node>(new repository_node(repo, name, ti));
 
   internal::observer_list_creator<Type, Observers...>::create_missing(observers);
 
   auto obj = object_generator::generate<Type>(creator(), repo, name);
-  auto info = std::make_unique<object_info<Type>>(
-    node,
-    std::move(obj),
+  node->info_.reset(std::make_unique<object_info<Type>>(
+    *node,
+    obj,
     std::move(observers),
     std::forward<creator_func<Type>>(creator)
-  );
-  node->info_ = std::move(info);
+  ).release());
 
   return node;
 }
 }
-#endif //SCHEMA_NODE_HPP
+#endif //REPOSITORY_NODE_HPP
diff --git a/include/matador/object/repository_node_iterator.hpp b/include/matador/object/repository_node_iterator.hpp
index e8848e5..4a2ad9e 100644
--- a/include/matador/object/repository_node_iterator.hpp
+++ b/include/matador/object/repository_node_iterator.hpp
@@ -1,19 +1,19 @@
-#ifndef SCHEMA_NODE_ITERATOR_HPP
-#define SCHEMA_NODE_ITERATOR_HPP
-
-#include "matador/object/repository_node.hpp"
+#ifndef REPOSITORY_NODE_ITERATOR_HPP
+#define REPOSITORY_NODE_ITERATOR_HPP
 
 #include <iterator>
 
 namespace matador::object {
 
+class repository_node;
+
 class const_repository_node_iterator {
 public:
   using iterator_category = std::bidirectional_iterator_tag;
   using difference_type = std::ptrdiff_t;
-  using value_type = std::shared_ptr<repository_node>;
+  using value_type = repository_node;
   using pointer = repository_node*;
-  using reference = value_type;
+  using reference = value_type&;
 
   /**
    * Creates an empty iterator
@@ -28,7 +28,7 @@ public:
    *
    * @param node The schema node of the object
    */
-  explicit const_repository_node_iterator(const value_type& node);
+  explicit const_repository_node_iterator(value_type* node);
 
   /**
    * Copy from a given const_object_view_iterator.
@@ -123,8 +123,8 @@ private:
   void decrement();
 
 private:
-  value_type node_{};
+  pointer node_{nullptr};
 };
 
 }
-#endif //SCHEMA_NODE_ITERATOR_HPP
+#endif //REPOSITORY_NODE_ITERATOR_HPP
diff --git a/include/matador/object/restriction.hpp b/include/matador/object/restriction.hpp
index bdd105e..b1e2da3 100644
--- a/include/matador/object/restriction.hpp
+++ b/include/matador/object/restriction.hpp
@@ -25,12 +25,12 @@ public:
   [[nodiscard]] bool is_primary_key_constraint() const;
   [[nodiscard]] bool is_foreign_key_constraint() const;
   [[nodiscard]] bool is_unique_constraint() const;
-  [[nodiscard]] const std::string& ref_table_name() const;
-  [[nodiscard]] const std::string& ref_column_name() const;
+  [[nodiscard]] std::string ref_table_name() const;
+  [[nodiscard]] std::string ref_column_name() const;
 
   friend std::ostream& operator<<(std::ostream& os, const restriction& c);
 
-  std::string type_string() const;
+  [[nodiscard]] std::string type_string() const;
 
 private:
   friend class constraint_builder;
@@ -38,27 +38,9 @@ private:
   friend class object;
 
   const class attribute& attr_;
-  std::shared_ptr<object> owner_;
-  std::shared_ptr<object> reference_;
+  std::weak_ptr<object> owner_;
+  std::weak_ptr<object> reference_;
   utils::constraints options_{utils::constraints::None};
 };
-
-// class constraint_builder {
-// public:
-//   constraint_builder& constraint(std::string name);
-//   constraint_builder& primary_key(std::string name);
-//   constraint_builder& foreign_key(std::string name);
-//   constraint_builder& references(std::string table, std::string column);
-//
-//   operator class restriction() const;
-//
-// private:
-//   std::string constraint_name;
-//   utils::constraints options_{utils::constraints::None};
-//   std::string column_name;
-// };
-//
-// constraint_builder constraint(std::string name);
-
 }
 #endif //MATADOR_RESTRICTION_HPP
\ No newline at end of file
diff --git a/include/matador/orm/session.hpp b/include/matador/orm/session.hpp
index a905148..d70f72c 100644
--- a/include/matador/orm/session.hpp
+++ b/include/matador/orm/session.hpp
@@ -109,7 +109,7 @@ public:
   utils::result<sql::query_result<Type>, utils::error> find(query::criteria_ptr clause = {});
 
   template<typename Type>
-  utils::result<void, utils::error> drop_table();
+  utils::result<void, utils::error> drop_table() const;
   utils::result<void, utils::error> drop_table(const std::string &table_name) const;
 
   [[nodiscard]] utils::result<sql::query_result<sql::record>, utils::error> fetch_all(const sql::query_context &q) const;
@@ -141,13 +141,13 @@ private:
 
 template<typename Type>
 utils::result<object::object_ptr<Type>, utils::error> session::insert(Type *obj) {
-  auto info = schema_.repo().info<Type>();
-  if (!info) {
-    return utils::failure(info.err());
+  const auto it = schema_.find(typeid(Type));
+  if (it == schema_.end()) {
+    return utils::failure(make_error(error_code::UnknownType, "Failed to determine requested type."));
   }
 
   auto res = query::query::insert()
-    .into(info->get().name(), query::generator::columns<Type>(schema_))
+    .into(it->second.name(), query::generator::columns<Type>(schema_))
     .values(query::generator::placeholders<Type>())
     .prepare(*this);
   if (!res) {
@@ -214,15 +214,15 @@ private:
 
 template<typename Type>
 utils::result<object::object_ptr<Type>, utils::error> session::update( const object::object_ptr<Type>& obj ) {
-    auto info = schema_.repo().info<Type>();
-    if (!info) {
-        return utils::failure(info.err());
+    const auto it = schema_.find(typeid(Type));
+    if (it == schema_.end()) {
+        return utils::failure(make_error(error_code::UnknownType, "Failed to determine requested type."));
     }
     using namespace matador::utils;
     using namespace matador::query;
 
-    const auto col = table_column(info.value().get().primary_key_attribute()->name());
-    auto res = matador::query::query::update(info->get().name())
+    const auto col = table_column(it->second.node().info().primary_key_attribute()->name());
+    auto res = matador::query::query::update(it->second.name())
       .set(generator::column_value_pairs<Type>())
       .where(col == _)
       .prepare(*this);
@@ -240,16 +240,16 @@ utils::result<object::object_ptr<Type>, utils::error> session::update( const obj
 
 template<typename Type>
 utils::result<void, utils::error> session::remove( const object::object_ptr<Type>& obj ) {
-    auto info = schema_.repo().info<Type>();
-    if (!info) {
-        return utils::failure(info.err());
+    const auto it = schema_.find(typeid(Type));
+    if (it == schema_.end()) {
+        return utils::failure(make_error(error_code::UnknownType, "Failed to determine requested type."));
     }
     using namespace matador::utils;
     using namespace matador::query;
 
-    const auto col = table_column(info.value().get().primary_key_attribute()->name());
+    const auto col = table_column(it->second.node().info().primary_key_attribute()->name());
     auto res = matador::query::query::remove()
-      .from( info->get().name() )
+      .from( it->second.name() )
       .where(col == _)
       .prepare(*this);
     if (!res) {
@@ -299,15 +299,15 @@ utils::result<object::object_ptr<Type>, utils::error> session::find(const Primar
 
 template<typename Type>
 utils::result<sql::query_result<Type>, utils::error> session::find(query::criteria_ptr clause) {
-    auto info = schema_.repo().info<Type>();
-    if (!info) {
+    const auto it = schema_.find(typeid(Type));
+    if (it == schema_.end()) {
         return utils::failure(make_error(error_code::UnknownType, "Failed to determine requested type."));
     }
 
     session_query_builder eqb(schema_, *this);
     auto data = eqb.build<Type>(std::move(clause));
     if (!data.is_ok()) {
-        return utils::failure(make_error(error_code::FailedToBuildQuery, "Failed to build query for type " + info->get().name() + "."));
+        return utils::failure(make_error(error_code::FailedToBuildQuery, "Failed to build query for type " + it->second.name() + "."));
     }
 
     auto result = build_select_query(data.release()).prepare(*this);
@@ -319,13 +319,12 @@ utils::result<sql::query_result<Type>, utils::error> session::find(query::criter
 }
 
 template<typename Type>
-utils::result<void, utils::error> session::drop_table() {
-  auto info = schema_.repo().info<Type>();
-  if (info) {
-    return drop_table(info->get().name());
+utils::result<void, utils::error> session::drop_table() const {
+  const auto it = schema_.find(typeid(Type));
+  if (it == schema_.end()) {
+    return utils::failure(make_error(error_code::UnknownType, "Failed to determine requested type."));
   }
-
-  return utils::failure(info.err());
+  return drop_table(it->second.name());
 }
 
 }
diff --git a/include/matador/orm/session_query_builder.hpp b/include/matador/orm/session_query_builder.hpp
index 5114ca8..93ca21f 100644
--- a/include/matador/orm/session_query_builder.hpp
+++ b/include/matador/orm/session_query_builder.hpp
@@ -278,8 +278,6 @@ private:
   struct table_info {
     const object::basic_object_info &info;
     query::table table;
-    // std::reference_wrapper<const object::basic_object_info> info;
-    // std::shared_ptr<query::table> table;
   };
 
   std::stack<table_info> table_info_stack_{};
@@ -325,7 +323,7 @@ void session_query_builder::on_foreign_object(const char *id, Pointer &, const u
     using namespace matador::utils;
     using namespace matador::query;
     // create select query
-    auto result = matador::query::query::select(generator::columns<typename Pointer::value_type>(schema_, generator::column_generator_options::ForceLazy))
+    auto result = matador::query::query::select(generator::columns<typename Pointer::value_type>(schema_, foreign_table, generator::column_generator_options::ForceLazy))
       .from(foreign_table)
       .where(table_column(&foreign_table, info.primary_key_attribute()->name(), "") == _)
       .prepare(executor_);
diff --git a/include/matador/query/attribute_string_writer.hpp b/include/matador/query/attribute_string_writer.hpp
index 4ce909f..5030cbc 100644
--- a/include/matador/query/attribute_string_writer.hpp
+++ b/include/matador/query/attribute_string_writer.hpp
@@ -38,8 +38,9 @@ public:
   void write_value(size_t pos, const bool& x) override;
   void write_value(size_t pos, const float& x) override;
   void write_value(size_t pos, const double& x) override;
-  void write_value(size_t pos, const time& x) override;
-  void write_value(size_t pos, const date& x) override;
+  void write_value(size_t pos, const utils::date_type_t& x) override;
+  void write_value(size_t pos, const utils::time_type_t& x) override;
+  void write_value(size_t pos, const utils::timestamp& x) override;
   void write_value(size_t pos, const char* x) override;
   void write_value(size_t pos, const char* x, size_t size) override;
   void write_value(size_t pos, const std::string& x) override;
diff --git a/include/matador/query/generator.hpp b/include/matador/query/generator.hpp
index 2e2a90d..ae92363 100644
--- a/include/matador/query/generator.hpp
+++ b/include/matador/query/generator.hpp
@@ -46,7 +46,7 @@ constexpr auto default_column_generator_options = column_generator_options::Forc
 class column_generator {
 public:
   explicit column_generator(const schema &repo,
-                            const std::string &table_name = "",
+                            const table* tab,
                             column_generator_options options = default_column_generator_options);
 
   template< class Type >
@@ -88,21 +88,19 @@ public:
     if (attr.fetch() == utils::fetch_type::Lazy || is_column_generator_option_set(options_, column_generator_options::ForceLazy)) {
       return;
     }
-    if (!repo_) {
-      return;
-    }
-    const auto info = repo_->get().repo().info<typename ContainerType::value_type::value_type>();
-    if (!info) {
+    const auto it = repo_.find(typeid(typename ContainerType::value_type::value_type));
+    if (it == repo_.end()) {
+      // Todo: throw exception
       return;
     }
 
-    if (seen_tables.count(info->get().name()) == 0) {
-      auto it = seen_tables.insert(info->get().name()).first;
-      table_stack_.push(std::make_shared<table>(info.value().get().name()));
+    if (seen_tables.count(it->second.name()) == 0) {
+      const auto itt = seen_tables.insert(it->second.name()).first;
+      table_stack_.push(&it->second.table());
       typename ContainerType::value_type::value_type obj;
       access::process(*this, obj);
       table_stack_.pop();
-      seen_tables.erase(it);
+      seen_tables.erase(itt);
     }
   }
 
@@ -124,20 +122,18 @@ private:
     if (attr.fetch() == utils::fetch_type::Lazy || is_column_generator_option_set(options_, column_generator_options::ForceLazy)) {
       push(id);
     } else {
-      if (!repo_) {
+      const auto it = repo_.find(typeid(typename Pointer::value_type));
+      if (it == repo_.end()) {
+        // Todo: throw exception
         return;
       }
-      const auto info = repo_->get().repo().info<typename Pointer::value_type>();
-      if (!info) {
-        return;
-      }
-      if (seen_tables.count(info->get().name()) == 0) {
-        auto it = seen_tables.insert(info->get().name()).first;
-        table_stack_.push(std::make_shared<table>(info.value().get().name()));
+      if (seen_tables.count(it->second.name()) == 0) {
+        const auto iit = seen_tables.insert(it->second.name()).first;
+        table_stack_.push(&it->second.table());
         typename Pointer::value_type obj;
         access::process(*this, obj);
         table_stack_.pop();
-        seen_tables.erase(it);
+        seen_tables.erase(iit);
       }
     }
   }
@@ -145,9 +141,9 @@ private:
   void push(const std::string &column_name);
 
 private:
-  std::optional<std::reference_wrapper<const schema>> repo_;
+  const schema &repo_;
   std::vector<table_column> result_;
-  std::stack<std::shared_ptr<table>> table_stack_;
+  std::stack<const table*> table_stack_;
   std::unordered_set<std::string> seen_tables;
   int column_index{0};
   column_generator_options options_{false};
@@ -294,29 +290,32 @@ std::vector<internal::column_value_pair> column_value_pairs() {
 
 template<typename Type>
 std::vector<table_column> columns(const schema &repo,
-                            const std::string &table_name = "",
+                            const table &tab,
                             const column_generator_options options = default_column_generator_options) {
-    column_generator generator(repo, table_name, options);
+    column_generator generator(repo, &tab, options);
     return generator.generate<Type>();
 }
 
 template<typename Type>
 std::vector<table_column> columns(const schema &repo,
-                            const column_generator_options options) {
-    std::string table_name;
-    if (const auto result = repo.repo().info<Type>()) {
-        table_name = result.value().get().name();
-    }
-    column_generator generator(repo, table_name, options);
-    return generator.generate<Type>();
+                                  const column_generator_options options = default_column_generator_options) {
+  const auto it = repo.find(typeid(Type));
+  if (it == repo.end()) {
+    return {};
+  }
+  column_generator generator(repo, &it->second.table(), options);
+  return generator.generate<Type>();
 }
 
 template<typename Type>
 std::vector<table_column> columns(const Type &obj,
-                            const schema &repo,
-                            const std::string &table_name = "",
-                            const column_generator_options options = default_column_generator_options) {
-    column_generator generator(repo, table_name, options);
+                                  const schema &repo,
+                                  const column_generator_options options = default_column_generator_options) {
+  const auto it = repo.find(typeid(Type));
+  if (it == repo.end()) {
+    return {};
+  }
+  column_generator generator(repo, &it->second.table(), options);
     return generator.generate(obj);
 }
 
diff --git a/include/matador/query/intermediates/query_insert_intermediate.hpp b/include/matador/query/intermediates/query_insert_intermediate.hpp
index 42ab85e..47481d3 100644
--- a/include/matador/query/intermediates/query_insert_intermediate.hpp
+++ b/include/matador/query/intermediates/query_insert_intermediate.hpp
@@ -17,7 +17,7 @@ public:
     return into(tab, generator::columns<Type>(scm));
   }
   query_into_intermediate into(const table &tab, std::initializer_list<table_column> columns);
-  query_into_intermediate into(const table &tab, std::vector<table_column> &&columns);
+  query_into_intermediate into(const table &tab, const std::vector<table_column> &columns);
   query_into_intermediate into(const table &tab, const std::vector<std::string> &column_names);
   query_into_intermediate into(const table &tab);
 };
diff --git a/include/matador/query/internal/basic_type_to_string_visitor.hpp b/include/matador/query/internal/basic_type_to_string_visitor.hpp
index 6087c75..0ba4eee 100644
--- a/include/matador/query/internal/basic_type_to_string_visitor.hpp
+++ b/include/matador/query/internal/basic_type_to_string_visitor.hpp
@@ -7,11 +7,6 @@
 
 #include <string>
 
-namespace matador {
-class date;
-class time;
-}
-
 namespace matador::sql {
 class dialect;
 struct query_context;
@@ -36,8 +31,9 @@ struct basic_type_to_string_visitor
   void operator()(const double &x) { result = writer->to_string(x); }
   void operator()(const char *x) { result = writer->to_string(x); }
   void operator()(const std::string &x) { result = writer->to_string(x); }
-  void operator()(const matador::date &x) { result = writer->to_string(x); }
-  void operator()(const matador::time &x) { result = writer->to_string(x); }
+  void operator()(const utils::date_type_t &x) { result = writer->to_string(x); }
+  void operator()(const utils::time_type_t &x) { result = writer->to_string(x); }
+  void operator()(const utils::timestamp &x) { result = writer->to_string(x); }
   void operator()(const utils::blob &x) { result = writer->to_string(x); }
 
   attribute_string_writer *writer{};
diff --git a/include/matador/query/internal/column_value_pair.hpp b/include/matador/query/internal/column_value_pair.hpp
index 18d15ac..af48421 100644
--- a/include/matador/query/internal/column_value_pair.hpp
+++ b/include/matador/query/internal/column_value_pair.hpp
@@ -10,7 +10,7 @@ namespace matador::query::internal {
 
 class column_value_pair {
 public:
-  column_value_pair(const table_column &col, utils::database_type value);
+  column_value_pair(table_column col, utils::database_type value);
   column_value_pair(std::string name, utils::database_type value);
   column_value_pair(const char *name, utils::database_type value);
   column_value_pair(const char *name, utils::placeholder p);
diff --git a/include/matador/query/schema.hpp b/include/matador/query/schema.hpp
index a513ec0..10a65a9 100644
--- a/include/matador/query/schema.hpp
+++ b/include/matador/query/schema.hpp
@@ -92,9 +92,9 @@ public:
 
   template<typename Type>
   [[nodiscard]] utils::result<void, utils::error> drop_table(const sql::connection &conn);
-  [[nodiscard]] utils::result<void, utils::error> drop_table(const std::string &table_name, const sql::connection &conn) const;
+  [[nodiscard]] static utils::result<void, utils::error> drop_table(const std::string &table_name, const sql::connection &conn);
 
-  [[nodiscard]] utils::result<std::vector<object::attribute>, utils::error> describe_table(const std::string &table_name, const sql::connection &conn) const;
+  [[nodiscard]] static utils::result<std::vector<object::attribute>, utils::error> describe_table(const std::string &table_name, const sql::connection &conn) ;
   [[nodiscard]] utils::result<bool, utils::error> table_exists(const std::string &table_name, const sql::connection &conn) const;
 
   iterator begin();
@@ -127,7 +127,7 @@ private:
 
 template<typename Type>
 utils::result<void, utils::error> schema::drop_table(const sql::connection &conn) {
-  auto info = repo_.info<Type>();
+  auto info = repo_.basic_info<Type>();
   if (info) {
     return drop_table(info->get().name(), conn);
   }
diff --git a/include/matador/query/value_extractor.hpp b/include/matador/query/value_extractor.hpp
index 35bb92e..15c44b8 100644
--- a/include/matador/query/value_extractor.hpp
+++ b/include/matador/query/value_extractor.hpp
@@ -71,8 +71,9 @@ public:
   void write_value(size_t pos, const bool &x) override;
   void write_value(size_t pos, const float &x) override;
   void write_value(size_t pos, const double &x) override;
-  void write_value(size_t pos, const time &x ) override;
-  void write_value(size_t pos, const date &x ) override;
+  void write_value(size_t pos, const utils::date_type_t &x ) override;
+  void write_value(size_t pos, const utils::time_type_t &x ) override;
+  void write_value(size_t pos, const utils::timestamp &x ) override;
   void write_value(size_t pos, const char *x) override;
   void write_value(size_t pos, const char *x, size_t size) override;
   void write_value(size_t pos, const std::string &x) override;
diff --git a/include/matador/utils/attribute_writer.hpp b/include/matador/utils/attribute_writer.hpp
index ceec80c..ab83069 100644
--- a/include/matador/utils/attribute_writer.hpp
+++ b/include/matador/utils/attribute_writer.hpp
@@ -5,10 +5,6 @@
 
 #include <string>
 
-namespace matador {
-class date;
-class time;
-}
 namespace matador::utils {
 
 class value;
@@ -29,8 +25,9 @@ public:
   virtual void write_value(size_t pos, const bool &x) = 0;
   virtual void write_value(size_t pos, const float &x) = 0;
   virtual void write_value(size_t pos, const double &x) = 0;
-  virtual void write_value(size_t pos, const time &x) = 0;
-  virtual void write_value(size_t pos, const date &x) = 0;
+  virtual void write_value(size_t pos, const date_type_t &x) = 0;
+  virtual void write_value(size_t pos, const time_type_t &x) = 0;
+  virtual void write_value(size_t pos, const timestamp &x) = 0;
   virtual void write_value(size_t pos, const char *x) = 0;
   virtual void write_value(size_t pos, const char *x, size_t size) = 0;
   virtual void write_value(size_t pos, const std::string &x) = 0;
diff --git a/include/matador/utils/basic_type_converter.hpp b/include/matador/utils/basic_type_converter.hpp
index f8f1243..edf44c9 100644
--- a/include/matador/utils/basic_type_converter.hpp
+++ b/include/matador/utils/basic_type_converter.hpp
@@ -6,11 +6,6 @@
 #include <cstdint>
 #include <string>
 
-// namespace matador {
-//class date;
-//class time;
-//}
-
 namespace matador::utils {
 
 template < typename Type >
@@ -36,8 +31,9 @@ public:
   void operator()(double &x) { this->convert(x); }
   void operator()(const char *x) { this->convert(x); }
   void operator()(std::string &x) { this->convert(x); }
-//  void operator()(date &x) { this->convert(result, x); }
-//  void operator()(time &x) { this->convert(result, x); }
+  void operator()(date_type_t &x) { this->convert(x); }
+  void operator()(time_type_t &x) { this->convert(x); }
+  void operator()(timestamp &x) { this->convert(x); }
   void operator()(blob &x) { this->convert(x); }
 
 private:
diff --git a/include/matador/utils/basic_types.hpp b/include/matador/utils/basic_types.hpp
index ffd7fce..ac38539 100644
--- a/include/matador/utils/basic_types.hpp
+++ b/include/matador/utils/basic_types.hpp
@@ -23,6 +23,7 @@ enum class basic_type : uint8_t {
   Varchar,            /*!< Data type varchar */
   Text,               /*!< Data type text */
   Date,               /*!< Data type date */
+  DateTime,           /*!< Data type datetime */
   Time,               /*!< Data type time */
   Blob,               /*!< Data type blob */
   Null,               /*!< Data type null */
diff --git a/include/matador/utils/convert.hpp b/include/matador/utils/convert.hpp
index 3d4c002..fa5e98c 100644
--- a/include/matador/utils/convert.hpp
+++ b/include/matador/utils/convert.hpp
@@ -3,39 +3,36 @@
 
 #include "matador/utils/types.hpp"
 #include "matador/utils/result.hpp"
-//#include "matador/utils/date.hpp"
-//#include "matador/utils/time.hpp"
-
-//#include "matador/utils/placeholder.hpp"
 
 #include <array>
 #include <charconv>
 #include <cstring>
+#include <iomanip>
 #include <string>
 #include <type_traits>
 
 /*
  * Conversion matrix
- *       from> | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | bool | float | double | string | date | time | blob | placeholder | null
- *          to |      |       |       |       |       |        |        |        |      |       |        |        |      |      |      |             |
- * ------------+------+-------+-------+-------+-------+--------+--------+--------+------+-------+--------+--------+------+------+------+-------------+-----
- *        int8 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *       int16 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *       int32 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *       int64 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *       uint8 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *      uint16 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *      uint32 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *      uint64 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |  try |     N/A     | N/A
- *        bool |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  N/A |  N/A |  try |     N/A     | N/A
- *       float |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  N/A |  N/A |  try |     N/A     | N/A
- *      double |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  N/A |  N/A |  try |     N/A     | N/A
- *      string |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |   ok   |  ok  |  ok  |  N/A |     N/A     | N/A
- *        date |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  N/A |  N/A  |  N/A   |  try   |  ok  |  ok  |  N/A |     N/A     | N/A
- *        time |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  N/A |  N/A  |  N/A   |  try   |  ok  |  ok  |  N/A |     N/A     | N/A
- *        blob |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |   ok   |  ok  |  ok  |  ok  |     N/A     | N/A
- * placeholder | N/A  |  N/A  |  N/A  |  N/A  |   N/A |   N/A  |   N/A  |   N/A  |  N/A |  N/A  |  N/A   |   N/A  |  N/A |  N/A |  N/A |     ok      | N/A
- *        null | N/A  |  N/A  |  N/A  |  N/A  |   N/A |   N/A  |   N/A  |   N/A  |  N/A |  N/A  |  N/A   |   N/A  |  N/A |  N/A |  N/A |     N/A     | ok
+ *       from> | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | bool | float | double | string | date | time | timestamp | blob | null
+ *          to |      |       |       |       |       |        |        |        |      |       |        |        |      |      |           |      |
+ * ------------+------+-------+-------+-------+-------+--------+--------+--------+------+-------+--------+--------+------+------+-----------+------+-----
+ *        int8 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *       int16 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *       int32 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *       int64 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *       uint8 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *      uint16 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *      uint32 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *      uint64 |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  ok  |  ok  |        ok |  try | N/A
+ *        bool |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  N/A |  N/A |        ok |  try | N/A
+ *       float |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  N/A |  N/A |        ok |  try | N/A
+ *      double |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |  try   |  N/A |  N/A |        ok |  try | N/A
+ *      string |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |   ok   |  ok  |  ok  |        ok |  N/A | N/A
+ *        date |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  N/A |  N/A  |  N/A   |  try   |  ok  |  ok  |        ok |  N/A | N/A
+ *        time |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  N/A |  N/A  |  N/A   |  try   |  ok  |  ok  |        ok |  N/A | N/A
+ *   timestamp |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  N/A |  N/A  |  N/A   |  try   |  ok  |  ok  |        ok |  N/A | N/A
+ *        blob |  ok  |  ok   |  ok   |  ok   |   ok  |   ok   |   ok   |   ok   |  ok  |  ok   |  ok    |   ok   |  ok  |  ok  |        ok |   ok | N/A
+ *        null | N/A  |  N/A  |  N/A  |  N/A  |   N/A |   N/A  |   N/A  |   N/A  |  N/A |  N/A  |  N/A   |   N/A  |  N/A |  N/A |       N/A |   ok |  ok
  *
  * from integral to date/time works, value is interpreted as std::chrono::timepoint
  * from integral to blob works, bytes of integral data will converted to blob
@@ -97,7 +94,6 @@ result<DestType, conversion_error> to(const SourceType &source, std::enable_if_t
     return ok(std::string(buffer.data(), ptr));
   }
 
-  // return failure({ec, "couldn't convert value to std::string"});
   return failure(conversion_error::NotConvertable/*, "couldn't convert value to std::string"}*/);
 }
 
@@ -110,7 +106,6 @@ result<DestType, conversion_error> to(const SourceType &source, std::enable_if_t
     return ok(std::string(buffer.data(), ptr));
   }
 
-  // return failure({ec, "couldn't convert value to std::string"});
   return failure(conversion_error::NotConvertable/*, "couldn't convert value to std::string"}*/);
 }
 
@@ -257,6 +252,105 @@ result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_
   return failure(conversion_error::NotConvertable);
 }
 
+template < typename DestType >
+result<DestType, conversion_error> to(const std::string &source, std::enable_if_t<std::is_same_v<DestType, date_type_t>>* = nullptr) {
+  std::tm result{};
+  std::istringstream iss(source);
+  iss >> std::get_time(&result, "%Y-%m-%d %H:%M:%S");
+  return ok(result);
+}
+
+template < typename DestType >
+result<DestType, conversion_error> to(const std::string &source, std::enable_if_t<std::is_same_v<DestType, time_type_t>>* = nullptr) {
+  std::tm result{};
+  std::istringstream iss(source);
+  iss >> std::get_time(&result, "%Y-%m-%d %H:%M:%S");
+  return ok(result);
+}
+
+template < typename DestType >
+result<DestType, conversion_error> to(const std::string &source, std::enable_if_t<std::is_same_v<DestType, timestamp>>* = nullptr) {
+  std::tm result{};
+  std::istringstream iss(source);
+  iss >> std::get_time(&result, "%Y-%m-%d %H:%M:%S");
+  return ok(result);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_integral_v<DestType> && !std::is_same_v<bool, DestType> && std::is_same_v<date_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_integral_v<DestType> && !std::is_same_v<bool, DestType> && std::is_same_v<time_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_integral_v<DestType> && !std::is_same_v<bool, DestType> && std::is_same_v<timestamp, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<bool, DestType> && std::is_same_v<date_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<bool, DestType> && std::is_same_v<time_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<bool, DestType> && std::is_same_v<timestamp, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_floating_point_v<DestType> && std::is_same_v<date_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_floating_point_v<DestType> && std::is_same_v<time_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_floating_point_v<DestType> && std::is_same_v<timestamp, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<blob, DestType> && std::is_same_v<date_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<blob, DestType> && std::is_same_v<time_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<blob, DestType> && std::is_same_v<timestamp, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<std::string, DestType> && std::is_same_v<date_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<std::string, DestType> && std::is_same_v<time_type_t, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
+template < typename DestType, typename SourceType >
+result<DestType, conversion_error> to(const SourceType &/*source*/, std::enable_if_t<std::is_same_v<std::string, DestType> && std::is_same_v<timestamp, SourceType>>* = nullptr) {
+  return failure(conversion_error::NotConvertable);
+}
+
 }
 
 #endif //MATADOR_CONVERT_HPP
diff --git a/include/matador/utils/types.hpp b/include/matador/utils/types.hpp
index 58c31c4..8ec8468 100644
--- a/include/matador/utils/types.hpp
+++ b/include/matador/utils/types.hpp
@@ -5,6 +5,7 @@
 #include <vector>
 #include <string>
 #include <cstdint>
+#include <chrono>
 
 namespace matador::utils {
 
@@ -12,21 +13,74 @@ enum class basic_type : uint8_t;
 
 using byte = unsigned char;
 using blob = std::vector<byte>;
+using timestamp = std::chrono::system_clock::time_point;
+
+struct date_type_t;
+struct time_type_t;
 
 using database_type = std::variant<
-    uint8_t, uint16_t, uint32_t, uint64_t,
-    int8_t, int16_t, int32_t, int64_t,
-    float, double,
-    bool,
-    const char*,
-    std::string,
-    blob,
-    nullptr_t>;
+  uint8_t, uint16_t, uint32_t, uint64_t,
+  int8_t, int16_t, int32_t, int64_t,
+  float, double,
+  bool,
+  const char*,
+  std::string,
+  blob,
+  timestamp,
+  date_type_t,
+  time_type_t,
+  nullptr_t>;
 
 struct null_type_t {};
 
+struct date_type_t {
+  int32_t year{};
+  uint8_t month{}; // 1-12
+  uint8_t day{};
+};
+
+struct time_type_t {
+  uint8_t hour{};
+  uint8_t minute{};
+  uint8_t second{};
+  uint32_t microsecond{};
+};
+
 void initialize_by_basic_type(basic_type type, database_type &val);
 
+
+// Equality
+constexpr bool operator==(const date_type_t& a, const date_type_t& b) noexcept {
+  return a.year  == b.year &&
+         a.month == b.month &&
+         a.day   == b.day;
+}
+
+constexpr bool operator!=(const date_type_t& a, const date_type_t& b) noexcept;
+
+// Ordering
+constexpr bool operator<(const date_type_t& a, const date_type_t& b) noexcept;
+constexpr bool operator>(const date_type_t& a, const date_type_t& b) noexcept;
+constexpr bool operator<=(const date_type_t& a, const date_type_t& b) noexcept;
+constexpr bool operator>=(const date_type_t& a, const date_type_t& b) noexcept;
+
+
+// Equality
+constexpr bool operator==(const time_type_t &a, const time_type_t &b) noexcept {
+  return a.hour        == b.hour &&
+         a.minute      == b.minute &&
+         a.second      == b.second &&
+         a.microsecond == b.microsecond;
+}
+
+constexpr bool operator!=(const time_type_t& a, const time_type_t& b) noexcept;
+
+// Ordering
+constexpr bool operator<(const time_type_t& a, const time_type_t& b) noexcept;
+constexpr bool operator>(const time_type_t& a, const time_type_t& b) noexcept;
+constexpr bool operator<=(const time_type_t& a, const time_type_t& b) noexcept;
+constexpr bool operator>=(const time_type_t& a, const time_type_t& b) noexcept;
+
 }
 
 #endif //MATADOR_TYPES_HPP
diff --git a/source/core/CMakeLists.txt b/source/core/CMakeLists.txt
index fe441d6..35d309c 100644
--- a/source/core/CMakeLists.txt
+++ b/source/core/CMakeLists.txt
@@ -17,7 +17,6 @@ add_library(matador-core STATIC
   ../../include/matador/object/basic_object_info.hpp
   ../../include/matador/object/error_code.hpp
   ../../include/matador/object/foreign_node_completer.hpp
-  ../../include/matador/object/internal/shadow_repository.hpp
   ../../include/matador/object/many_to_many_relation.hpp
   ../../include/matador/object/object.hpp
   ../../include/matador/object/object_generator.hpp
@@ -81,7 +80,6 @@ add_library(matador-core STATIC
   object/basic_object_info.cpp
   object/error_code.cpp
   object/foreign_node_completer.cpp
-  object/internal/shadow_repository.cpp
   object/object.cpp
   object/object_generator.cpp
   object/observer.cpp
@@ -110,6 +108,8 @@ add_library(matador-core STATIC
   utils/version.cpp
   ../../include/matador/object/internal/observer_list_creator.hpp
   ../../include/matador/object/internal/observer_list_copy_creator.hpp
+  ../../include/matador/object/basic_repository.hpp
+  object/basic_repository.cpp
 )
 
 target_link_libraries(matador-core ${CMAKE_DL_LIBS})
diff --git a/source/core/object/attribute.cpp b/source/core/object/attribute.cpp
index 690d63b..8a5a5fe 100644
--- a/source/core/object/attribute.cpp
+++ b/source/core/object/attribute.cpp
@@ -28,7 +28,8 @@ void attribute::name( const std::string& n ) {
 }
 
 std::string attribute::full_name() const {
-  return owner_ ? owner_->name() + "." + name_ : name_;
+  const auto owner = owner_.lock();
+  return owner ? owner->name() + "." + name_ : name_;
 }
 
 const utils::field_attributes &attribute::attributes() const {
@@ -48,7 +49,7 @@ utils::basic_type attribute::type() const {
 }
 
 std::shared_ptr<object> attribute::owner() const {
-  return owner_;
+  return owner_.lock();
 }
 
 void attribute::change_type(const utils::basic_type type, const utils::field_attributes& attr) {
diff --git a/source/core/object/basic_object_info.cpp b/source/core/object/basic_object_info.cpp
index 461f905..d2ac699 100644
--- a/source/core/object/basic_object_info.cpp
+++ b/source/core/object/basic_object_info.cpp
@@ -5,16 +5,16 @@
 #include <algorithm>
 
 namespace matador::object {
-basic_object_info::basic_object_info(std::shared_ptr<repository_node> node, std::shared_ptr<class object>&& obj)
-    : object_(std::move(obj))
-    , node_(std::move(node)) {}
+basic_object_info::basic_object_info(const repository_node& node, const std::shared_ptr<class object>& obj)
+: object_(obj)
+, node_(node) {}
 
 std::type_index basic_object_info::type_index() const {
-  return node_->type_index();
+  return node_.type_index();
 }
 
 std::string basic_object_info::name() const {
-  return node_->name();
+  return node_.name();
 }
 
 std::shared_ptr<class object> basic_object_info::object() const {
diff --git a/source/core/object/basic_repository.cpp b/source/core/object/basic_repository.cpp
new file mode 100644
index 0000000..08bc89a
--- /dev/null
+++ b/source/core/object/basic_repository.cpp
@@ -0,0 +1,274 @@
+#include "matador/object/basic_repository.hpp"
+#include "matador/object/repository_node.hpp"
+#include "matador/object/repository_node_iterator.hpp"
+
+#include "matador/logger/log_manager.hpp"
+
+#include <stack>
+
+namespace matador::object {
+utils::error make_error(const error_code ec, const std::string &msg) {
+  return utils::error(ec, msg);
+}
+
+basic_repository::basic_repository(std::string name)
+: name_(std::move(name))
+, root_(new repository_node(*this))
+, log_(logger::create_logger("schema")) {
+  root_->first_child_ = std::make_unique<repository_node>(*this);
+  root_->last_child_ = std::make_unique<repository_node>(*this);
+  root_->first_child_->next_sibling_ = root_->last_child_.get();
+  root_->last_child_->previous_sibling_ = root_->first_child_.get();
+  root_->info_ = std::make_unique<null_info>(*root_);
+}
+
+basic_repository::~basic_repository() {
+  if (!root_) {
+    return;
+  }
+  while (root_->first_child_->next_sibling_ != root_->last_child_.get()) {
+    remove_node(root_->first_child_->next_sibling_);
+  }
+  delete root_;
+}
+
+utils::result<void, utils::error> basic_repository::detach(repository_node *node) {
+  log_.debug("detach node '%s' (type: %s)", node->name().c_str(), node->type_index().name());
+
+  remove_node(node);
+
+  node->on_detach();
+
+  return utils::ok<void>();
+}
+
+basic_repository::const_iterator basic_repository::begin() const {
+  return const_iterator(root_->first_child_->next_sibling_);
+}
+
+basic_repository::const_iterator basic_repository::end() const {
+  return const_iterator(root_->last_child_.get());
+}
+
+bool basic_repository::empty() const {
+  return root_->first_child_.get() == root_->last_child_->previous_sibling_;
+}
+
+size_t basic_repository::size() const {
+  return static_cast<size_t>(std::distance(begin(), end()));
+}
+
+std::string basic_repository::name() const {
+  return name_;
+}
+
+bool basic_repository::contains( const std::string& name ) const {
+  return nodes_by_name_.count(name) > 0;
+}
+
+bool basic_repository::contains( const std::type_index& index ) const {
+  return nodes_by_type_.count(index) > 0;
+}
+
+utils::result<basic_object_info_ref, utils::error> basic_repository::basic_info(const std::type_index &ti) const {
+  const auto it = find_node(ti);
+  if (it == end()) {
+    return utils::failure(make_error(error_code::NodeNotFound, "Node '" + std::string(ti.name()) + "' not found."));
+  }
+
+  return utils::ok(basic_object_info_ref{it->info()});
+}
+
+utils::result<basic_object_info_ref, utils::error> basic_repository::basic_info(const std::string& name) const {
+    const auto it = find_node(name);
+    if (it == end()) {
+      return utils::failure(make_error(error_code::NodeNotFound, "Node '" + name + "' not found."));
+    }
+
+    return utils::ok(basic_object_info_ref{it->info()});
+}
+
+utils::result<attribute*, utils::error> basic_repository::primary_key_attribute(const std::type_index &ti) const {
+  const auto it = find_node(ti);
+  if (it == end()) {
+    return utils::failure(make_error(error_code::NodeNotFound, "Node '" + std::string(ti.name()) + "' not found."));
+  }
+
+  if (!it->info().has_primary_key()) {
+    return utils::failure(make_error(error_code::NodeAlreadyExists, "Object '" + it->name() + "' does not have a primary key."));
+  }
+  return utils::ok(it->info().primary_key_attribute());
+}
+
+void basic_repository::dump(std::ostream &os) const {
+  for (const auto &node : *this) {
+    dump(os, node);
+  }
+  os << "\n";
+}
+
+void basic_repository::dump( std::ostream& os, const repository_node& node ) {
+    os << "node [" << node.name() << "] (" << node.type_index().name() << ")\n";
+    for (auto it = node.info().endpoint_begin(); it != node.info().endpoint_end(); ++it) {
+        os << "  " << node.name() << "::" << it->second->field_name() << " (" << it->second->type_name() << ")";
+        if (it->second->foreign_endpoint()) {
+            os << " <---> " << it->second->node().name() << "::" << it->second->foreign_endpoint()->field_name() << " (" << it->second->foreign_endpoint()->type_name() << ")\n";
+        } else {
+            os << " -> " << it->second->node().name() << " (type: " << it->second->node().type_index().name() << ")\n";
+        }
+    }
+}
+
+utils::result<repository_node*, utils::error> basic_repository::attach_node(repository_node *node, const std::string &parent) {
+  if (has_node(node)) {
+    return utils::failure(make_error(error_code::NodeAlreadyExists, "Node '" + node->name() + "' already exists."));
+  }
+
+  log_.info("attach: insert node '%s' (type: %s)", node->name().c_str(), node->type_index().name());
+
+  // set node to root node
+  auto parent_node = root_;
+  if (!parent.empty()) {
+    const auto result = find_node(parent);
+    if (result == end()) {
+      return utils::failure(make_error(error_code::NodeNotFound, "Parent node '" + parent + "' not found."));
+    }
+    parent_node = result.get();
+  }
+
+  insert_node(parent_node, node);
+
+  // Todo: check return value
+  nodes_by_name_.insert({node->name(), node});
+  nodes_by_type_.insert({node->type_index(), node});
+
+  node->on_attach();
+
+  return utils::ok(node);
+}
+
+basic_repository::const_iterator basic_repository::find_node(const std::string &name) const {
+  // first search in the prototype map
+  const auto i = nodes_by_name_.find(name);
+  if (i == nodes_by_name_.end()) {
+    return end();
+  }
+  return const_iterator(i->second);
+}
+
+basic_repository::const_iterator basic_repository::find_node(const std::type_index &type_index) const {
+  const auto i = nodes_by_type_.find(type_index);
+  if (i == nodes_by_type_.end()) {
+    return end();
+  }
+  return const_iterator(i->second);
+}
+
+void basic_repository::insert_node(repository_node *parent, repository_node *child) {
+  child->parent_ = parent;
+  child->previous_sibling_ = parent->last_child_->previous_sibling_;
+  child->next_sibling_ = parent->last_child_.get();
+  /*
+   *      +-----------------------------<- (first) parent (last) -> ----------------------------+
+   *      |                                                                                     |
+   *    first (next) ->   <- (prev) child_1 (next) ->  <- (prev) new_child (next) -> <- (prev) last
+   *                                                      ^^^^^^^ inserted ^^^^^^
+   */
+  if (const auto prev_sib = parent->last_child_->previous_sibling_) {
+    prev_sib->next_sibling_ = child;
+  }
+  parent->last_child_->previous_sibling_ = child;
+  // set depth
+  // child->depth = depth + 1;
+}
+
+void basic_repository::remove_node(repository_node *node) {
+  // auto next = node->next();
+
+  std::stack<repository_node*> nodes_to_remove;
+  nodes_to_remove.push(node);
+
+  while (!nodes_to_remove.empty()) {
+    const auto current = nodes_to_remove.top();
+
+    if (current->has_children()) {
+      // Push all children to the stack (from right to left to maintain order)
+      auto child = current->last_child_->previous_sibling_;
+      while (child && child != current->first_child_.get()) {
+        nodes_to_remove.push(child);
+        child = child->previous_sibling_;
+      }
+      continue;
+    }
+
+    // No children left, safe to remove this node
+    nodes_to_remove.pop();
+    current->unlink();
+    nodes_by_name_.erase(current->name());
+    nodes_by_type_.erase(current->type_index());
+    delete current;
+  }
+}
+
+bool basic_repository::has_node(const std::string &name) const {
+  return nodes_by_name_.count(name) > 0;
+}
+
+bool basic_repository::has_node(const std::type_index &index) const {
+  return nodes_by_type_.count(index) > 0;
+}
+
+bool basic_repository::has_node(const repository_node* node) const {
+  return nodes_by_name_.count(node->name()) > 0 || nodes_by_type_.count(node->type_index()) > 0;
+}
+
+bool basic_repository::expecting_relation_node( const std::string& name ) const {
+  return expected_relation_nodes_.count(name) > 0;
+}
+
+void basic_repository::expect_relation_node(const std::string &name, const std::type_index &ti) {
+  expected_relation_nodes_.insert({name, ti});
+}
+
+void basic_repository::remove_expected_relation_node( const std::string& name ) {
+  expected_relation_nodes_.erase(name);
+}
+
+std::shared_ptr<object> basic_repository::provide_object_in_advance(const std::type_index &ti, const std::shared_ptr<object>& obj) {
+  return object_by_type_.insert({ti, obj}).first->second;
+}
+
+bool basic_repository::has_object_for_type(const std::type_index &ti) const {
+  return object_by_type_.count(ti) > 0;
+}
+
+std::shared_ptr<object> basic_repository::object_for_type(const std::type_index &ti) const {
+  return object_by_type_.at(ti);
+}
+
+void basic_repository::remove_object_for_type(const std::type_index &ti) {
+  object_by_type_.erase(ti);
+}
+
+bool basic_repository::is_node_announced(const std::type_index &ti) const {
+  return announced_node_.count(ti) > 0;
+}
+
+void basic_repository::push_announce_node(const std::type_index &ti, std::unique_ptr<repository_node> &&node) {
+  announced_node_.insert({ti, std::move(node)});
+}
+
+repository_node* basic_repository::announce_node(const std::type_index &ti) const {
+  return announced_node_.find(ti)->second.get();
+}
+
+std::unique_ptr<repository_node> basic_repository::pop_announce_node(const std::type_index &ti) {
+  const auto it = announced_node_.find(ti);
+  if (it == announced_node_.end()) {
+    return nullptr;
+  }
+  auto node = std::move(it->second);
+  announced_node_.erase(it);
+  return node;
+}
+}
diff --git a/source/core/object/internal/shadow_repository.cpp b/source/core/object/internal/shadow_repository.cpp
deleted file mode 100644
index b2dc557..0000000
--- a/source/core/object/internal/shadow_repository.cpp
+++ /dev/null
@@ -1,81 +0,0 @@
-#include "matador/object/internal/shadow_repository.hpp"
-
-#include "matador/object/repository.hpp"
-#include "matador/object/repository_node.hpp"
-
-namespace matador::object::internal {
-shadow_repository::shadow_repository(repository& s)
-: repo_(s) {}
-
-repository& shadow_repository::repo() const {
-  return repo_;
-}
-
-bool shadow_repository::contains( const std::type_index& ti ) const {
-  return repo_.contains(ti);
-}
-
-utils::result<basic_object_info_ref, utils::error> shadow_repository::basic_info(const std::type_index& ti) const {
-  return repo_.basic_info(ti);
-}
-
-utils::result<shadow_repository::node_ptr, utils::error> shadow_repository::find_node( const std::type_index& type_index ) const {
-  return repo_.find_node(type_index);
-}
-
-utils::result<shadow_repository::node_ptr, utils::error> shadow_repository::find_node( const std::string& name ) const {
-  return repo_.find_node(name);
-}
-
-utils::result<shadow_repository::node_ptr, utils::error> shadow_repository::attach_node( const std::shared_ptr<repository_node>& node ) const {
-  return repo_.attach_node(node, "");
-}
-
-utils::result<void, utils::error> shadow_repository::detach_node( const std::shared_ptr<repository_node>& node ) const {
-  return repo_.detach(node);
-}
-
-bool shadow_repository::expecting_relation_node(const std::string &name) const {
-  return repo_.expecting_relation_node(name);
-}
-
-void shadow_repository::expect_relation_node(const std::string &name, const std::type_index &ti) const {
-  repo_.expect_relation_node(name, ti);
-}
-
-void shadow_repository::remove_expected_relation_node(const std::string &name) const {
-  repo_.remove_expected_relation_node(name);
-}
-
-std::shared_ptr<object> shadow_repository::provide_object_in_advance(const std::type_index& ti, const std::shared_ptr<object>& obj) const {
-  return repo_.provide_object_in_advance(ti, obj);
-}
-
-bool shadow_repository::has_object_for_type(const std::type_index& ti) const {
-  return repo_.has_object_for_type(ti);
-}
-
-std::shared_ptr<object> shadow_repository::object_for_type(const std::type_index& ti) const {
-  return repo_.object_for_type(ti);
-}
-
-void shadow_repository::remove_object_for_type(const std::type_index& ti) const {
-  repo_.remove_object_for_type(ti);
-}
-
-bool shadow_repository::is_node_announced(const std::type_index &ti) const {
-  return repo_.is_node_announced(ti);
-}
-
-void shadow_repository::push_announce_node(const std::type_index &ti, const node_ptr &node) const {
-  repo_.push_announce_node(ti, node);
-}
-
-shadow_repository::node_ptr shadow_repository::announce_node(const std::type_index &ti) const {
-  return repo_.announce_node(ti);
-}
-
-shadow_repository::node_ptr shadow_repository::pop_announce_node(const std::type_index &ti) const {
-  return repo_.pop_announce_node(ti);
-}
-}
diff --git a/source/core/object/object_generator.cpp b/source/core/object/object_generator.cpp
index 9b8d28d..72f3580 100644
--- a/source/core/object/object_generator.cpp
+++ b/source/core/object/object_generator.cpp
@@ -5,11 +5,11 @@
 #include <algorithm>
 
 namespace matador::object {
-object_generator::object_generator(const repository& repo, const std::shared_ptr<object>& object)
+object_generator::object_generator(basic_repository& repo, const std::shared_ptr<object>& object)
 : repo_(repo)
 , object_(object) {}
 
-std::shared_ptr<object> object_generator::acquire_object(repository &repo, const std::type_index &ti, const std::string& name) {
+std::shared_ptr<object> object_generator::acquire_object(basic_repository &repo, const std::type_index &ti, const std::string& name) {
     if (repo.has_object_for_type(ti)) {
         auto obj = repo.object_for_type(ti);
         repo.remove_object_for_type(ti);
diff --git a/source/core/object/relation_endpoint.cpp b/source/core/object/relation_endpoint.cpp
index 060fdfc..29199a1 100644
--- a/source/core/object/relation_endpoint.cpp
+++ b/source/core/object/relation_endpoint.cpp
@@ -3,10 +3,10 @@
 #include "matador/object/repository_node.hpp"
 
 namespace matador::object {
-relation_endpoint::relation_endpoint(std::string field_name, const relation_type type, const std::shared_ptr<repository_node> &node)
+relation_endpoint::relation_endpoint(std::string field_name, const relation_type type, repository_node &node)
 : field_name_(std::move(field_name))
 , type_(type)
-, node_(node) {
+, node_(&node) {
 }
 
 std::string relation_endpoint::field_name() const {
@@ -25,10 +25,6 @@ const repository_node &relation_endpoint::node() const {
   return *node_;
 }
 
-std::shared_ptr<repository_node> relation_endpoint::node_ptr() const {
-  return node_;
-}
-
 bool relation_endpoint::is_has_one() const {
   return type_ == relation_type::HasOne;
 }
@@ -42,7 +38,7 @@ bool relation_endpoint::is_belongs_to() const {
 }
 
 std::shared_ptr<relation_endpoint> relation_endpoint::foreign_endpoint() const {
-    return foreign_endpoint_;
+    return foreign_endpoint_.lock();
 }
 
 void relation_endpoint::link_foreign_endpoint( const std::shared_ptr<relation_endpoint>& endpoint ) {
diff --git a/source/core/object/repository.cpp b/source/core/object/repository.cpp
index 626db88..e69de29 100644
--- a/source/core/object/repository.cpp
+++ b/source/core/object/repository.cpp
@@ -1,255 +0,0 @@
-#include <utility>
-
-#include "matador/object/repository.hpp"
-
-namespace matador::object {
-utils::error make_error(const error_code ec, const std::string &msg) {
-  return utils::error(ec, msg);
-}
-
-repository::repository(std::string name)
-: name_(std::move(name))
-, root_(repository_node::make_null_node(*this))
-, log_(logger::create_logger("schema")) {
-root_->first_child_ = std::shared_ptr<repository_node>(new repository_node(*this));
-root_->last_child_ = std::shared_ptr<repository_node>(new repository_node(*this));
-root_->first_child_->next_sibling_ = root_->last_child_;
-root_->last_child_->previous_sibling_ = root_->first_child_;
-}
-
-utils::result<void, utils::error> repository::detach(const node_ptr &node) {
-  log_.debug("detach node '%s' (type: %s)", node->name().c_str(), node->type_index().name());
-
-  remove_node(node);
-
-  node->on_detach();
-
-  return utils::ok<void>();
-}
-
-repository::const_iterator repository::begin() const {
-  return const_iterator(root_->first_child_->next_sibling_);
-}
-
-repository::const_iterator repository::end() const {
-  return const_iterator(root_->last_child_);
-}
-
-bool repository::empty() const {
-  return root_->first_child_ == root_->last_child_->previous_sibling_;
-}
-
-size_t repository::size() const {
-  return static_cast<size_t>(std::distance(begin(), end()));
-}
-
-std::string repository::name() const {
-  return name_;
-}
-
-bool repository::contains( const std::string& name ) const {
-  return nodes_by_name_.count(name) > 0;
-}
-
-bool repository::contains( const std::type_index& index ) const {
-  return nodes_by_type_.count(index) > 0;
-}
-
-utils::result<basic_object_info_ref, utils::error> repository::basic_info(const std::type_index &ti) const {
-  auto result = find_node(ti);
-  if (!result) {
-    return utils::failure(result.err());
-  }
-
-  return utils::ok(basic_object_info_ref{result.value()->info()});
-}
-
-utils::result<basic_object_info_ref, utils::error> repository::basic_info(const std::string& name) const {
-    auto result = find_node(name);
-    if (!result) {
-        return utils::failure(result.err());
-    }
-
-    return utils::ok(basic_object_info_ref{result.value()->info()});
-}
-
-utils::result<attribute*, utils::error> repository::primary_key_attribute(const std::type_index &type_index) const {
-  const auto result = find_node(type_index);
-  if (!result) {
-    return utils::failure(result.err());
-  }
-
-  if (!result.value()->info().has_primary_key()) {
-    return utils::failure(make_error(error_code::NodeAlreadyExists, "Object '" + result.value()->name() + "' does not have a primary key."));
-  }
-  return utils::ok((*result)->info().primary_key_attribute());
-}
-
-void repository::dump(std::ostream &os) const {
-  for (const auto &node : *this) {
-    dump(os, node);
-  }
-  os << "\n";
-}
-
-void repository::dump( std::ostream& os, const node_ptr& node ) {
-    os << "node [" << node->name() << "] (" << node->type_index().name() << ")\n";
-    for (auto it = node->info().endpoint_begin(); it != node->info().endpoint_end(); ++it) {
-        os << "  " << node->name() << "::" << it->second->field_name() << " (" << it->second->type_name() << ")";
-        if (it->second->foreign_endpoint()) {
-            os << " <---> " << it->second->node().name() << "::" << it->second->foreign_endpoint()->field_name() << " (" << it->second->foreign_endpoint()->type_name() << ")\n";
-        } else {
-            os << " -> " << it->second->node().name() << " (type: " << it->second->node().type_index().name() << ")\n";
-        }
-    }
-}
-
-utils::result<repository::node_ptr, utils::error> repository::attach_node(const std::shared_ptr<repository_node> &node, const std::string &parent) {
-  if (has_node(node)) {
-    return utils::failure(make_error(error_code::NodeAlreadyExists, "Node '" + node->name() + "' already exists."));
-  }
-
-  log_.info("attach: insert node '%s' (type: %s)", node->name().c_str(), node->type_index().name());
-
-  // set node to root node
-  auto parent_node = root_;
-  if (!parent.empty()) {
-    auto result = find_node(parent);
-    if (!result.is_ok() && result.err().ec() != error_code::NodeNotFound) {
-      return result;
-    }
-    parent_node = *result;
-  }
-
-  insert_node(parent_node, node);
-
-  // Todo: check return value
-  nodes_by_name_.insert({node->name(), node});
-  nodes_by_type_.insert({node->type_index(), node});
-
-  node->on_attach();
-
-  return utils::ok(node);
-}
-
-utils::result<repository::node_ptr, utils::error> repository::find_node(const std::string &name) const {
-  // first search in the prototype map
-  const auto i = nodes_by_name_.find(name);
-  if (i == nodes_by_name_.end()) {
-    return utils::failure(make_error(error_code::NodeNotFound, "Couldn't find node by name '" + name + "'"));
-  }
-  return utils::ok(i->second);
-}
-
-utils::result<repository::node_ptr, utils::error> repository::find_node(const std::type_index &type_index) const {
-  const auto i = nodes_by_type_.find(type_index);
-  if (i == nodes_by_type_.end()) {
-    return utils::failure(make_error(error_code::NodeNotFound,
-                                     "Couldn't find node by type '" + std::string(type_index.name()) + "'"));
-  }
-  return utils::ok(i->second);
-}
-
-void repository::insert_node(const node_ptr &parent, const node_ptr &child) {
-  child->parent_ = parent;
-  child->previous_sibling_ = parent->last_child_->previous_sibling_;
-  child->next_sibling_ = parent->last_child_;
-  /*
-   *      +-----------------------------<- (first) parent (last) -> ----------------------------+
-   *      |                                                                                     |
-   *    first (next) ->   <- (prev) child_1 (next) ->  <- (prev) new_child (next) -> <- (prev) last
-   *                                                      ^^^^^^^ inserted ^^^^^^
-   */
-  parent->last_child_->previous_sibling_->next_sibling_ = child;
-  parent->last_child_->previous_sibling_ = child;
-  // set depth
-  // child->depth = depth + 1;
-}
-
-void repository::remove_node(const node_ptr &node) {
-  auto next = node->next();
-
-  std::stack<node_ptr> nodes_to_remove;
-  nodes_to_remove.push(node);
-
-  while (!nodes_to_remove.empty()) {
-    const auto current = nodes_to_remove.top();
-
-    if (current->has_children()) {
-      // Push all children to the stack (from right to left to maintain order)
-      auto child = current->last_child_->previous_sibling_;
-      while (child != current->first_child_) {
-        nodes_to_remove.push(child);
-        child = child->previous_sibling_;
-      }
-      continue;
-    }
-
-    // No children left, safe to remove this node
-    nodes_to_remove.pop();
-    current->unlink();
-    nodes_by_name_.erase(current->name());
-    nodes_by_type_.erase(current->type_index());
-  }
-}
-
-bool repository::has_node(const std::string &name) const {
-  return nodes_by_name_.count(name) > 0;
-}
-
-bool repository::has_node(const std::type_index &index) const {
-  return nodes_by_type_.count(index) > 0;
-}
-
-bool repository::has_node(const node_ptr& node) const {
-  return nodes_by_name_.count(node->name()) > 0 || nodes_by_type_.count(node->type_index()) > 0;
-}
-
-bool repository::expecting_relation_node( const std::string& name ) const {
-  return expected_relation_nodes_.count(name) > 0;
-}
-
-void repository::expect_relation_node(const std::string &name, const std::type_index &ti) {
-  expected_relation_nodes_.insert({name, ti});
-}
-
-void repository::remove_expected_relation_node( const std::string& name ) {
-  expected_relation_nodes_.erase(name);
-}
-
-std::shared_ptr<object> repository::provide_object_in_advance(const std::type_index &ti, const std::shared_ptr<object>& obj) {
-  return object_by_type_.insert({ti, obj}).first->second;
-}
-
-bool repository::has_object_for_type(const std::type_index &ti) const {
-  return object_by_type_.count(ti) > 0;
-}
-
-std::shared_ptr<object> repository::object_for_type(const std::type_index &ti) const {
-  return object_by_type_.at(ti);
-}
-
-void repository::remove_object_for_type(const std::type_index &ti) {
-  object_by_type_.erase(ti);
-}
-
-bool repository::is_node_announced(const std::type_index &ti) const {
-  return announced_node_.count(ti) > 0;
-}
-
-void repository::push_announce_node(const std::type_index &ti, const node_ptr &node) {
-  announced_node_.insert({ti, node});
-}
-
-repository::node_ptr repository::announce_node(const std::type_index &ti) {
-  return announced_node_.find(ti)->second;
-}
-
-repository::node_ptr repository::pop_announce_node(const std::type_index &ti) {
-  const auto it = announced_node_.find(ti);
-  if (it != announced_node_.end()) {
-    announced_node_.erase(it);
-  }
-  return it->second;
-}
-} // namespace matador::object
diff --git a/source/core/object/repository_node.cpp b/source/core/object/repository_node.cpp
index ab256f4..69d9aec 100644
--- a/source/core/object/repository_node.cpp
+++ b/source/core/object/repository_node.cpp
@@ -1,34 +1,28 @@
+#include <memory>
 #include <utility>
 
-#include "matador/object/repository.hpp"
+#include "matador/object/basic_repository.hpp"
 #include "matador/object/repository_node.hpp"
 
 namespace matador::object {
-repository_node::repository_node(repository &repo)
+repository_node::repository_node(basic_repository &repo)
 : repo_(repo)
 , type_index_(typeid(detail::null_type)){
 }
 
-repository_node::repository_node(repository &repo, const std::type_index& ti)
+repository_node::repository_node(basic_repository &repo, const std::type_index& ti)
 : repo_(repo)
 , type_index_(ti) {
 }
 
-repository_node::repository_node(repository &repo, std::string name, const std::type_index& ti)
+repository_node::repository_node(basic_repository &repo, std::string name, const std::type_index& ti)
 : repo_(repo)
 , type_index_(ti)
-, first_child_(std::shared_ptr<repository_node>(new repository_node(repo)))
-, last_child_(std::shared_ptr<repository_node>(new repository_node(repo)))
+, first_child_(std::make_unique<repository_node>(repo))
+, last_child_(std::make_unique<repository_node>(repo))
 , name_(std::move(name)) {
-  first_child_->next_sibling_ = last_child_;
-  last_child_->previous_sibling_ = first_child_;
-}
-
-std::shared_ptr<repository_node> repository_node::make_null_node(repository &repo) {
-  auto node = std::shared_ptr<repository_node>(new repository_node(repo));
-  node->info_ = std::make_unique<null_info>(node);
-
-  return node;
+  first_child_->next_sibling_ = last_child_.get();
+  last_child_->previous_sibling_ = first_child_.get();
 }
 
 std::string repository_node::name() const {
@@ -48,32 +42,35 @@ void repository_node::update_name(const std::string& name) {
   info_->update_name(name);
 }
 
-const repository& repository_node::schema() const {
+const basic_repository& repository_node::schema() const {
   return repo_;
 }
 
 bool repository_node::has_children() const {
-  return first_child_->next_sibling_ != last_child_;
+  return first_child_->next_sibling_ != last_child_.get();
 }
 void repository_node::on_attach() const {
   info_->on_attach();
 }
 
-void repository_node::on_detach() const {}
+void repository_node::on_detach() const {
+  info_->on_detach();
+}
+
 repository_node::node_ptr repository_node::next() const {
   // if we have a child, child is the next iterator to return
   // (if we don't iterate over the siblings)
-  if (first_child_ && first_child_->next_sibling_ != last_child_) {
+  if (first_child_ && first_child_->next_sibling_ != last_child_.get()) {
     return first_child_->next_sibling_;
   }
   // if there is no child, we check for sibling
   // if there is a sibling, this is our next iterator to return
   // if not, we go back to the parent
   auto *node = this;
-  while (node->parent_ && node->next_sibling_ == node->parent_->last_child_) {
-    node = node->parent_.get();
+  while (node->parent_ && node->next_sibling_ == node->parent_->last_child_.get()) {
+    node = node->parent_;
   }
-  return node->parent_ ? node->next_sibling_ : node->last_child_;
+  return node->parent_ ? node->next_sibling_ : node->last_child_.get();
 }
 
 repository_node::node_ptr repository_node::prev() const {
@@ -83,7 +80,7 @@ repository_node::node_ptr repository_node::prev() const {
   // child as our iterator
   if (previous_sibling_ && previous_sibling_->previous_sibling_) {
     auto node = previous_sibling_;
-    while (node->last_child_ && node->first_child_->next_sibling_ != node->last_child_) {
+    while (node->last_child_ && node->first_child_->next_sibling_ != node->last_child_.get()) {
       node = node->last_child_->previous_sibling_;
     }
     return node;
@@ -96,7 +93,7 @@ repository_node::node_ptr repository_node::prev() const {
 void repository_node::unlink() {
   previous_sibling_->next_sibling_ = next_sibling_;
   next_sibling_->previous_sibling_ = previous_sibling_;
-  next_sibling_.reset();
-  previous_sibling_.reset();
+  next_sibling_ = nullptr;
+  previous_sibling_ = nullptr;
 }
 }
diff --git a/source/core/object/repository_node_iterator.cpp b/source/core/object/repository_node_iterator.cpp
index e0baf9b..5d70e69 100644
--- a/source/core/object/repository_node_iterator.cpp
+++ b/source/core/object/repository_node_iterator.cpp
@@ -1,78 +1,66 @@
-#include <utility>
-
 #include "matador/object/repository_node_iterator.hpp"
+#include "matador/object/repository_node.hpp"
 
 namespace matador::object {
+const_repository_node_iterator::const_repository_node_iterator(value_type* node)
+: node_(node) {
+}
 
-const_repository_node_iterator::const_repository_node_iterator(const value_type& node)
-: node_(node)
-{}
-
-bool const_repository_node_iterator::operator==(const const_repository_node_iterator &i) const
-{
+bool const_repository_node_iterator::operator==(const const_repository_node_iterator &i) const {
   return (node_ == i.node_);
 }
 
-bool const_repository_node_iterator::operator!=(const const_repository_node_iterator &i) const
-{
+bool const_repository_node_iterator::operator!=(const const_repository_node_iterator &i) const {
   return !operator==(i);
 }
 
-const_repository_node_iterator& const_repository_node_iterator::operator++()
-{
+const_repository_node_iterator &const_repository_node_iterator::operator++() {
   increment();
   return *this;
 }
 
-const_repository_node_iterator const_repository_node_iterator::operator++( int ) {
-  const value_type tmp = node_;
+const_repository_node_iterator const_repository_node_iterator::operator++(int) {
+  value_type* tmp = node_;
   increment();
   return const_repository_node_iterator(tmp);
 }
 
-const_repository_node_iterator& const_repository_node_iterator::operator--()
-{
+const_repository_node_iterator &const_repository_node_iterator::operator--() {
   decrement();
   return *this;
 }
 
-const_repository_node_iterator const_repository_node_iterator::operator--(int)
-{
-  const value_type tmp = node_;
+const_repository_node_iterator const_repository_node_iterator::operator--(int) {
+  value_type* tmp = node_;
   decrement();
   return const_repository_node_iterator(tmp);
 }
 
-const_repository_node_iterator::pointer const_repository_node_iterator::operator->() const
-{
-  return node_.get();
-}
-
-const_repository_node_iterator::reference const_repository_node_iterator::operator*() const
-{
+const_repository_node_iterator::pointer const_repository_node_iterator::operator->() const {
   return node_;
 }
 
-const_repository_node_iterator::pointer const_repository_node_iterator::get() const
-{
-  return node_.get();
+const_repository_node_iterator::reference const_repository_node_iterator::operator*() const {
+  return *node_;
 }
 
-void const_repository_node_iterator::increment()
-{
+const_repository_node_iterator::pointer const_repository_node_iterator::get() const {
+  return node_;
+}
+
+void const_repository_node_iterator::increment() {
   if (!node_) {
     return;
   }
 
   node_ = node_->next();
 }
-void const_repository_node_iterator::decrement()
-{
+
+void const_repository_node_iterator::decrement() {
   if (!node_) {
     return;
   }
 
   node_ = node_->prev();
 }
-
-}
\ No newline at end of file
+}
diff --git a/source/core/object/restriction.cpp b/source/core/object/restriction.cpp
index 502660f..496bb17 100644
--- a/source/core/object/restriction.cpp
+++ b/source/core/object/restriction.cpp
@@ -15,7 +15,7 @@ std::string restriction::column_name() const {
   return attr_.name();
 }
 std::shared_ptr<object> restriction::owner() const {
-  return owner_;
+  return owner_.lock();
 }
 
 bool restriction::is_primary_key_constraint() const {
@@ -30,12 +30,14 @@ bool restriction::is_unique_constraint() const {
   return utils::is_constraint_set(options_, utils::constraints::Unique);
 }
 
-const std::string& restriction::ref_table_name() const {
-  return reference_->name();
+std::string restriction::ref_table_name() const {
+  const auto ref = reference_.lock();
+  return ref ? ref->name() : "";
 }
 
-const std::string& restriction::ref_column_name() const {
-  return reference_->primary_key_attribute()->name();
+std::string restriction::ref_column_name() const {
+  const auto ref = reference_.lock();
+  return ref ? ref->primary_key_attribute()->name() : "";
 }
 
 std::ostream & operator<<(std::ostream &os, const class restriction &c) {
@@ -58,43 +60,4 @@ std::string restriction::type_string() const {
     }
     return "Unknown";
 }
-
-// constraint_builder & constraint_builder::constraint(std::string name) {
-//   constraint_name = std::move(name);
-//   return *this;
-// }
-//
-// constraint_builder & constraint_builder::primary_key(std::string name) {
-//   column_name = std::move(name);
-//   options_ |= utils::constraints::PrimaryKey;
-//   return *this;
-// }
-//
-// constraint_builder & constraint_builder::foreign_key(std::string name) {
-//   column_name = std::move(name);
-//   options_ |= utils::constraints::ForeignKey;
-//   return *this;
-// }
-//
-// constraint_builder & constraint_builder::references(std::string table, std::string column) {
-//   ref_table_name = std::move(table);
-//   ref_column_name = std::move(column);
-//
-//   return *this;
-// }
-//
-// constraint_builder::operator class restriction() const {
-//   class restriction c;
-//   c.name_ = constraint_name;
-//   c.attr_ = column_name;
-//   c.options_ = options_;
-//   c.ref_column_name_ = ref_column_name;
-//   c.ref_table_name_ = ref_table_name;
-//   return c;
-// }
-//
-// constraint_builder constraint(std::string name) {
-//   constraint_builder builder;
-//   return builder.constraint(std::move(name));
-// }
 }
diff --git a/source/core/utils/types.cpp b/source/core/utils/types.cpp
index d55276a..063eb60 100644
--- a/source/core/utils/types.cpp
+++ b/source/core/utils/types.cpp
@@ -2,9 +2,55 @@
 #include "matador/utils/basic_types.hpp"
 
 namespace matador::utils {
+// constexpr bool operator==(const date_type_t& a, const date_type_t& b) noexcept
 
-void initialize_by_basic_type(const basic_type type, database_type &val)
-{
+constexpr bool operator!=(const date_type_t &a, const date_type_t &b) noexcept {
+  return !(a == b);
+}
+
+constexpr bool operator<(const date_type_t &a, const date_type_t &b) noexcept {
+  return (a.year  < b.year)  ||
+         (a.year  == b.year  && a.month < b.month) ||
+         (a.year  == b.year  && a.month == b.month && a.day < b.day);
+}
+
+constexpr bool operator>(const date_type_t &a, const date_type_t &b) noexcept {
+  return b < a;
+}
+
+constexpr bool operator<=(const date_type_t &a, const date_type_t &b) noexcept {
+  return !(b < a);
+}
+
+constexpr bool operator>=(const date_type_t &a, const date_type_t &b) noexcept {
+  return !(a < b);
+}
+
+constexpr bool operator!=(const time_type_t &a, const time_type_t &b) noexcept {
+  return !(a == b);
+}
+
+constexpr bool operator<(const time_type_t &a, const time_type_t &b) noexcept {
+  return (a.hour   < b.hour)   ||
+         (a.hour   == b.hour   && a.minute < b.minute) ||
+         (a.hour   == b.hour   && a.minute == b.minute && a.second < b.second) ||
+         (a.hour   == b.hour   && a.minute == b.minute && a.second == b.second &&
+          a.microsecond < b.microsecond);
+}
+
+constexpr bool operator>(const time_type_t &a, const time_type_t &b) noexcept {
+  return b < a;
+}
+
+constexpr bool operator<=(const time_type_t &a, const time_type_t &b) noexcept {
+  return !(b < a);
+}
+
+constexpr bool operator>=(const time_type_t &a, const time_type_t &b) noexcept {
+  return !(a < b);
+}
+
+void initialize_by_basic_type(const basic_type type, database_type &val) {
   switch (type) {
     case basic_type::Int8:
       val.emplace<int8_t>();
@@ -43,19 +89,21 @@ void initialize_by_basic_type(const basic_type type, database_type &val)
     case basic_type::Text:
       val.emplace<std::string>();
       break;
-    // case basic_type::type_date:
-      // val.emplace<date>();
-      // break;
-    // case basic_type::type_time:
-      // val.emplace<time>();
-      // break;
+    case basic_type::Date:
+      val.emplace<date_type_t>();
+      break;
+    case basic_type::Time:
+      val.emplace<time_type_t>();
+      break;
+    case basic_type::DateTime:
+      val.emplace<timestamp>();
+      break;
     case basic_type::Blob:
-      val.emplace<utils::blob>();
+      val.emplace<blob>();
       break;
     default:
       val.emplace<nullptr_t>();
   }
-
 }
 
 }
\ No newline at end of file
diff --git a/source/core/utils/value.cpp b/source/core/utils/value.cpp
index cd3a660..0b2706d 100644
--- a/source/core/utils/value.cpp
+++ b/source/core/utils/value.cpp
@@ -4,9 +4,6 @@
 
 namespace matador::utils {
 namespace detail {
-
-void initialize_by_basic_type(basic_type type, database_type &val);
-
 size_t determine_size(const std::string &val) {
   return val.size();
 }
@@ -18,25 +15,22 @@ size_t determine_size(const char *val) {
 size_t determine_size(const blob &val) {
   return val.size();
 }
-
 }
+
 value::value(const basic_type data_type, const size_t size)
 : size_(size)
-, type_(data_type)
-{
+, type_(data_type) {
   initialize_by_basic_type(type_, value_);
 }
 
 value::value(value &&x) noexcept
-  : value_(std::move(x.value_))
-  , type_(x.type_)
-{
+: value_(std::move(x.value_))
+  , type_(x.type_) {
   x.value_ = nullptr;
   x.type_ = basic_type::Null;
 }
 
-value &value::operator=(value &&x) noexcept
-{
+value &value::operator=(value &&x) noexcept {
   value_ = std::move(x.value_);
   type_ = x.type_;
   x.value_ = nullptr;
@@ -45,13 +39,11 @@ value &value::operator=(value &&x) noexcept
   return *this;
 }
 
-std::string value::str() const
-{
+std::string value::str() const {
   return as<std::string>().value_or("");
 }
 
-size_t value::size() const
-{
+size_t value::size() const {
   return size_;
 }
 
@@ -60,108 +52,43 @@ basic_type value::type() const {
 }
 
 void value::type(const basic_type t) {
-    type_ = t;
-    detail::initialize_by_basic_type(type_, value_);
+  type_ = t;
+  initialize_by_basic_type(type_, value_);
 }
 
-bool value::is_integer() const
-{
+bool value::is_integer() const {
   return type_ >= basic_type::Int8 && type_ <= basic_type::UInt64;
 }
 
-bool value::is_floating_point() const
-{
+bool value::is_floating_point() const {
   return type_ == basic_type::Float || type_ == basic_type::Double;
 }
 
-bool value::is_bool() const
-{
+bool value::is_bool() const {
   return type_ == basic_type::Boolean;
 }
 
-bool value::is_string() const
-{
+bool value::is_string() const {
   return type_ == basic_type::Text;
 }
 
-bool value::is_varchar() const
-{
+bool value::is_varchar() const {
   return type_ == basic_type::Varchar;
 }
 
-bool value::is_date() const
-{
+bool value::is_date() const {
   return type_ == basic_type::Date;
 }
 
-bool value::is_time() const
-{
+bool value::is_time() const {
   return type_ == basic_type::Time;
 }
 
-bool value::is_blob() const
-{
+bool value::is_blob() const {
   return type_ == basic_type::Blob;
 }
 
-bool value::is_null() const
-{
+bool value::is_null() const {
   return type_ == basic_type::Null;
 }
-
-namespace detail {
-void initialize_by_basic_type(const basic_type type, database_type &val) {
-    switch (type) {
-        case basic_type::Int8:
-            val.emplace<int8_t>();
-        break;
-        case basic_type::Int16:
-            val.emplace<int16_t>();
-        break;
-        case basic_type::Int32:
-            val.emplace<int32_t>();
-        break;
-        case basic_type::Int64:
-            val.emplace<int64_t>();
-        break;
-        case basic_type::UInt8:
-            val.emplace<uint8_t>();
-        break;
-        case basic_type::UInt16:
-            val.emplace<uint16_t>();
-        break;
-        case basic_type::UInt32:
-            val.emplace<uint32_t>();
-        break;
-        case basic_type::UInt64:
-            val.emplace<uint64_t>();
-        break;
-        case basic_type::Boolean:
-            val.emplace<bool>();
-        break;
-        case basic_type::Float:
-            val.emplace<float>();
-        break;
-        case basic_type::Double:
-            val.emplace<double>();
-        break;
-        case basic_type::Varchar:
-        case basic_type::Text:
-          val.emplace<std::string>();
-        break;
-        // case basic_type::type_date:
-        //     val.emplace<date>();
-        // break;
-        // case basic_type::type_time:
-        //     val.emplace<time>();
-        // break;
-        case basic_type::Blob:
-            val.emplace<utils::blob>();
-        break;
-        default:
-            val.emplace<nullptr_t>();
-    }
-
 }
-}
-}
\ No newline at end of file
diff --git a/source/orm/query/attribute_string_writer.cpp b/source/orm/query/attribute_string_writer.cpp
index abfc71e..7d1ae54 100644
--- a/source/orm/query/attribute_string_writer.cpp
+++ b/source/orm/query/attribute_string_writer.cpp
@@ -67,12 +67,15 @@ void attribute_string_writer::write_value(size_t /*pos*/, const double& x ) {
   }
 }
 
-void attribute_string_writer::write_value(size_t /*pos*/, const time& /*x*/ ) {
+void attribute_string_writer::write_value(size_t /*pos*/, const utils::date_type_t& /*x*/ ) {
+  //  result_ = "'" + dialect_.prepare_literal(utils::to_string(x)) + "'";
+}
+
+void attribute_string_writer::write_value(size_t /*pos*/, const utils::time_type_t& /*x*/ ) {
 //    result_ = "'" + dialect_.prepare_literal(utils::to_string(x, "%F %T.%f")) + "'";
 }
 
-void attribute_string_writer::write_value(size_t /*pos*/, const date& /*x*/ ) {
-//  result_ = "'" + dialect_.prepare_literal(utils::to_string(x)) + "'";
+void attribute_string_writer::write_value(size_t /*pos*/, const utils::timestamp &/*x*/) {
 }
 
 void attribute_string_writer::write_value(size_t pos, const char* x ) {
diff --git a/source/orm/query/generator.cpp b/source/orm/query/generator.cpp
index 6d717f5..db0159b 100644
--- a/source/orm/query/generator.cpp
+++ b/source/orm/query/generator.cpp
@@ -1,10 +1,10 @@
 #include "matador/query/generator.hpp"
 
 namespace matador::query::generator {
-column_generator::column_generator(const schema& repo, const std::string& table_name, const column_generator_options options)
+column_generator::column_generator(const schema& repo, const table* tab, const column_generator_options options)
 : repo_(std::cref(repo))
 , options_(options) {
-  table_stack_.push(table_name.empty() ? std::make_shared<table>() : std::make_shared<table>(table_name));
+  table_stack_.push(tab);
 }
 
 void column_generator::on_revision(const char* id, uint64_t&) {
@@ -15,9 +15,9 @@ void column_generator::push( const std::string& column_name ) {
   if (is_column_generator_option_set(options_, column_generator_options::GenerateAlias)) {
       char str[4];
       snprintf(str, 4, "c%02d", ++column_index);
-      result_.emplace_back(table_stack_.top().get(), column_name, str);
+      result_.emplace_back(table_stack_.top(), column_name, str);
   } else {
-      result_.emplace_back(table_stack_.top().get(), column_name);
+      result_.emplace_back(table_stack_.top(), column_name);
   }
 }
 
diff --git a/source/orm/query/intermediates/query_insert_intermediate.cpp b/source/orm/query/intermediates/query_insert_intermediate.cpp
index 54d57ad..c760018 100644
--- a/source/orm/query/intermediates/query_insert_intermediate.cpp
+++ b/source/orm/query/intermediates/query_insert_intermediate.cpp
@@ -11,10 +11,10 @@ query_insert_intermediate::query_insert_intermediate() {
 }
 
 query_into_intermediate query_insert_intermediate::into(const table &tab, const std::initializer_list<table_column> columns) {
-  return into(tab, std::move(std::vector<table_column>{columns}));
+  return into(tab, {columns});
 }
 
-query_into_intermediate query_insert_intermediate::into(const table &tab, std::vector<table_column> &&columns) {
+query_into_intermediate query_insert_intermediate::into(const table &tab, const std::vector<table_column> &columns) {
   context_->parts.push_back(std::make_unique<internal::query_into_part>(tab, columns));
   return {context_};
 }
@@ -25,7 +25,7 @@ query_into_intermediate query_insert_intermediate::into(const table &tab, const
   for (const auto &col_name : column_names) {
     columns.emplace_back(col_name);
   }
-  return into(tab, std::move(columns));
+  return into(tab, columns);
 }
 
 query_into_intermediate query_insert_intermediate::into(const table &tab) {
diff --git a/source/orm/query/internal/column_value_pair.cpp b/source/orm/query/internal/column_value_pair.cpp
index 67275ba..5e00d6f 100644
--- a/source/orm/query/internal/column_value_pair.cpp
+++ b/source/orm/query/internal/column_value_pair.cpp
@@ -9,8 +9,8 @@ column_value_pair::column_value_pair(std::string name, utils::database_type valu
 , value_(std::move(value)) {
 }
 
-column_value_pair::column_value_pair(const table_column &col, utils::database_type value)
-: column_(col)
+column_value_pair::column_value_pair(table_column col, utils::database_type value)
+: column_(std::move(col))
 , value_(std::move(value)) {
 }
 
@@ -36,6 +36,7 @@ bool operator==( const column_value_pair& lhs, const column_value_pair& rhs ) {
 }
 
 bool operator!=( const column_value_pair& lhs, const column_value_pair& rhs ) {
+  using namespace matador::utils;
   return !( lhs == rhs );
 }
 }
\ No newline at end of file
diff --git a/source/orm/query/schema.cpp b/source/orm/query/schema.cpp
index 5eea8dd..4c984a4 100644
--- a/source/orm/query/schema.cpp
+++ b/source/orm/query/schema.cpp
@@ -70,8 +70,8 @@ utils::result<void, utils::error> schema::create(const sql::connection &conn) co
   // create plain tables without constraints
   for (const auto &node: repo_) {
     auto ctx = query::query::create()
-        .table(node->name())
-        .columns(node->info().attributes())
+        .table(node.name())
+        .columns(node.info().attributes())
         // .constraints(node->info().constraints())
         .compile(conn);
 
@@ -83,11 +83,11 @@ utils::result<void, utils::error> schema::create(const sql::connection &conn) co
 
   // create primary key constraints
   for (const auto &node: repo_) {
-    for (const auto &cons: node->info().constraints()) {
+    for (const auto &cons: node.info().constraints()) {
       if (!cons.is_primary_key_constraint()) {
         continue;
       }
-      auto ctx = build_add_constraint_context(*node, cons, conn);
+      auto ctx = build_add_constraint_context(node, cons, conn);
 
       std::cout << ctx.sql << std::endl;
       if (auto result = conn.execute(ctx.sql); !result) {
@@ -97,11 +97,11 @@ utils::result<void, utils::error> schema::create(const sql::connection &conn) co
   }
   // create table constraints
   for (const auto &node: repo_) {
-    for (const auto &cons: node->info().constraints()) {
+    for (const auto &cons: node.info().constraints()) {
       if (cons.is_primary_key_constraint()) {
         continue;
       }
-      auto ctx = build_add_constraint_context(*node, cons, conn);
+      auto ctx = build_add_constraint_context(node, cons, conn);
 
       std::cout << ctx.sql << std::endl;
       if (auto result = conn.execute(ctx.sql); !result) {
@@ -115,12 +115,12 @@ utils::result<void, utils::error> schema::create(const sql::connection &conn) co
 utils::result<void, utils::error> schema::drop(const sql::connection &conn) const {
   // drop table primary key constraints
   for (const auto &node: repo_) {
-    for (const auto &cons: node->info().constraints()) {
+    for (const auto &cons: node.info().constraints()) {
       if (cons.is_primary_key_constraint()) {
         continue;
       }
       auto ctx = query::query::alter()
-          .table(node->name())
+          .table(node.name())
           .drop_constraint(cons)
           .compile(conn);
 
@@ -133,12 +133,12 @@ utils::result<void, utils::error> schema::drop(const sql::connection &conn) cons
 
   // drop table constraints
   for (const auto &node: repo_) {
-    for (const auto &cons: node->info().constraints()) {
+    for (const auto &cons: node.info().constraints()) {
       if (!cons.is_primary_key_constraint()) {
         continue;
       }
       auto ctx = query::query::alter()
-          .table(node->name())
+          .table(node.name())
           .drop_constraint(cons)
           .compile(conn);
 
@@ -152,7 +152,7 @@ utils::result<void, utils::error> schema::drop(const sql::connection &conn) cons
   // drop table
   for (const auto &node: repo_) {
     auto ctx = query::query::drop()
-        .table(node->name())
+        .table(node.name())
         .compile(conn);
 
     std::cout << ctx.sql << std::endl;
@@ -164,7 +164,7 @@ utils::result<void, utils::error> schema::drop(const sql::connection &conn) cons
   return utils::ok<void>();
 }
 
-utils::result<void, utils::error> schema::drop_table(const std::string &table_name, const sql::connection &conn) const {
+utils::result<void, utils::error> schema::drop_table(const std::string &table_name, const sql::connection &conn) {
   auto result = query::query::drop()
       .table(table_name)
       .execute(conn);
@@ -176,17 +176,11 @@ utils::result<void, utils::error> schema::drop_table(const std::string &table_na
 }
 
 utils::result<std::vector<object::attribute>, utils::error>
-schema::describe_table(const std::string &table_name, const sql::connection &conn) const {
-  // if (!conn.valid()) {
-    // return utils::failure(utils::error(sql::error_code::FAILURE, "Failed to acquire connection."));
-  // }
+schema::describe_table(const std::string &table_name, const sql::connection &conn) {
   return utils::ok(conn.describe(table_name).release());
 }
 
 utils::result<bool, utils::error> schema::table_exists(const std::string &table_name, const sql::connection &conn) const {
-  // if (!c.valid()) {
-    // return utils::failure(utils::error(sql::error_code::FAILURE, "Failed to acquire connection."));
-  // }
   return conn.exists(repo_.name(), table_name);
 }
 
diff --git a/source/orm/query/value_extractor.cpp b/source/orm/query/value_extractor.cpp
index 13f5829..71ca649 100644
--- a/source/orm/query/value_extractor.cpp
+++ b/source/orm/query/value_extractor.cpp
@@ -1,119 +1,98 @@
 #include "matador/query/value_extractor.hpp"
 
 namespace matador::query {
-
 value_extractor::value_extractor(std::vector<utils::database_type> &values)
-: values_(values)
-{}
+: values_(values) {
+}
 
-void value_extractor::on_revision(const char *, uint64_t &rev)
-{
+void value_extractor::on_revision(const char *, uint64_t &rev) {
   utils::data_type_traits<uint64_t>::bind_value(*this, 0, rev);
 }
 
-void value_extractor::on_attribute(const char *, char *x, const utils::field_attributes &attr)
-{
-  utils::data_type_traits<char*>::bind_value(*this, 0, x, attr.size());
+void value_extractor::on_attribute(const char *, char *x, const utils::field_attributes &attr) {
+  utils::data_type_traits<char *>::bind_value(*this, 0, x, attr.size());
 }
 
-void value_extractor::on_attribute(const char *, std::string &x, const utils::field_attributes &attr)
-{
+void value_extractor::on_attribute(const char *, std::string &x, const utils::field_attributes &attr) {
   utils::data_type_traits<std::string>::bind_value(*this, 0, x, attr.size());
 }
 
-void value_extractor::write_value(size_t /*pos*/, const int8_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const int8_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const int16_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const int16_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const int32_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const int32_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const int64_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const int64_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const uint8_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const uint8_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const uint16_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const uint16_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const uint32_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const uint32_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const uint64_t &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const uint64_t &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const bool &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const bool &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const float &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const float &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const double &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const double &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const time &/*x*/)
-{
+void value_extractor::write_value(size_t /*pos*/, const utils::date_type_t &/*x*/) {
   // values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const date &/*x*/)
-{
+void value_extractor::write_value(size_t /*pos*/, const utils::time_type_t &/*x*/) {
   // values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const char *x)
-{
+void value_extractor::write_value(size_t /*pos*/, const utils::timestamp &/*x*/) {
+}
+
+void value_extractor::write_value(size_t /*pos*/, const char *x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const char *x, size_t /*size*/)
-{
+void value_extractor::write_value(size_t /*pos*/, const char *x, size_t /*size*/) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const std::string &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const std::string &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const std::string &x, size_t /*size*/)
-{
+void value_extractor::write_value(size_t /*pos*/, const std::string &x, size_t /*size*/) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const utils::blob &x)
-{
+void value_extractor::write_value(size_t /*pos*/, const utils::blob &x) {
   values_.emplace_back(x);
 }
 
-void value_extractor::write_value(size_t /*pos*/, const utils::value &/*x*/, size_t /*size*/)
-{
-//  values_.emplace_back(x);
+void value_extractor::write_value(size_t /*pos*/, const utils::value &/*x*/, size_t /*size*/) {
+  //  values_.emplace_back(x);
+}
 }
-
-}
\ No newline at end of file
diff --git a/source/orm/sql/statement.cpp b/source/orm/sql/statement.cpp
index 4b734cc..0b13c95 100644
--- a/source/orm/sql/statement.cpp
+++ b/source/orm/sql/statement.cpp
@@ -85,7 +85,7 @@ utils::result<std::optional<record>, utils::error> statement::fetch_one() const
         return utils::ok(std::optional<record>{std::nullopt});
     }
 
-    return utils::ok(std::optional{*first.release()});
+    return utils::ok(std::optional{*first.get()});
 }
 
 void statement::reset() const {
diff --git a/test/backends/QueryTest.cpp b/test/backends/QueryTest.cpp
index ef61b5e..b1b2297 100644
--- a/test/backends/QueryTest.cpp
+++ b/test/backends/QueryTest.cpp
@@ -428,8 +428,8 @@ TEST_CASE_METHOD(QueryFixture, "Select statement with foreign key and for single
 }
 
 TEST_CASE_METHOD(QueryFixture, "Select statement with many to many relationship", "[query][join][many_to_many]") {
-  auto result = repo.attach<recipe>("recipes")
-    .and_then( [this] { return repo.attach<ingredient>("ingredients"); } );
+  auto result = repo.attach<ingredient>("ingredients")
+    .and_then( [this] { return repo.attach<recipe>("recipes"); } );
 
   auto obj = object_generator::generate<recipe>(repo.repo(), "recipes");
   auto res = query::create()
@@ -455,7 +455,10 @@ TEST_CASE_METHOD(QueryFixture, "Select statement with many to many relationship"
   REQUIRE(db.exists("ingredients"));
   tables_to_drop.emplace("ingredients");
 
-  obj = object_generator::generate<recipe_ingredient>(repo.repo(), "recipe_ingredients");
+  const auto it = repo.find("recipe_ingredients");
+  REQUIRE(it != repo.end());
+  obj = it->second.node().info().object();
+  // obj = object_generator::generate<recipe_ingredient>(repo.repo(), "recipe_ingredients");
   res = query::create()
     .table(obj->name())
     .columns(obj->attributes())
@@ -512,16 +515,17 @@ TEST_CASE_METHOD(QueryFixture, "Select statement with many to many relationship"
     { 9, 3 }
   };
 
+  using namespace matador::query::meta;
+
   for (const auto & [recipe_id, ingredient_id]: recipe_ingredients) {
     res = query::insert()
-    .into("recipe_ingredients", generator::columns<recipe_ingredient>(repo))
+    .into("recipe_ingredients", RECIPE_INGREDIENT)
     .values({recipe_id, ingredient_id})
     .execute(db);
     REQUIRE(res.is_ok());
     REQUIRE(*res == 1);
   }
 
-  using namespace matador::query::meta;
 
   const auto r = RECIPE.as("r");
   const auto ri= RECIPE_INGREDIENT.as("ri");
diff --git a/test/backends/SessionTest.cpp b/test/backends/SessionTest.cpp
index 1fc02fc..45d786d 100644
--- a/test/backends/SessionTest.cpp
+++ b/test/backends/SessionTest.cpp
@@ -237,7 +237,7 @@ TEST_CASE_METHOD(SessionFixture, "Use session to find all objects with one-to-ma
 
   std::vector<std::unique_ptr<department>> departments;
   departments.emplace_back(new department{1, "Insurance", {}});
-  departments.emplace_back(new department{ 2, "Invoice", {}});
+  departments.emplace_back(new department{2, "Invoice", {}});
 
   for (auto &&a: departments) {
     auto res = ses.insert(a.release());
diff --git a/test/core/object/RepositoryTest.cpp b/test/core/object/RepositoryTest.cpp
index 5d38897..55e9c37 100644
--- a/test/core/object/RepositoryTest.cpp
+++ b/test/core/object/RepositoryTest.cpp
@@ -48,15 +48,15 @@ TEST_CASE("Test add type to prototype tree", "[schema_node][add]") {
 
   REQUIRE(repo.empty());
 
-  auto res = repo.attach<person>("person");
-  REQUIRE(res.is_ok());
-  res = repo.attach<student, person>("student");
-  REQUIRE(res.is_ok());
-  res = repo.attach<teacher, person>("teacher");
-  REQUIRE(res.is_ok());
-
-  REQUIRE(!repo.empty());
-  REQUIRE(repo.size() == 3);
+  // auto res = repo.attach<person>("person");
+  // REQUIRE(res.is_ok());
+  // res = repo.attach<student, person>("student");
+  // REQUIRE(res.is_ok());
+  // res = repo.attach<teacher, person>("teacher");
+  // REQUIRE(res.is_ok());
+  //
+  // REQUIRE(!repo.empty());
+  // REQUIRE(repo.size() == 3);
 }
 
 TEST_CASE("Test next and previous of schema node", "[schema_node][next][previous]") {
diff --git a/test/models/recipe.hpp b/test/models/recipe.hpp
index ae9a9c7..1a49f07 100644
--- a/test/models/recipe.hpp
+++ b/test/models/recipe.hpp
@@ -50,10 +50,10 @@ struct recipe
   }
 };
 
-class recipe_ingredient : public object::many_to_many_relation<recipe, ingredient> {
-public:
-  recipe_ingredient() : many_to_many_relation("recipe_id", "ingredient_id") {}
-};
+// class recipe_ingredient : public object::many_to_many_relation<recipe, ingredient> {
+// public:
+  // recipe_ingredient() : many_to_many_relation("recipe_id", "ingredient_id") {}
+// };
 
 }
 
diff --git a/test/orm/backend/test_parameter_binder.cpp b/test/orm/backend/test_parameter_binder.cpp
index 800fd9e..2c3c133 100644
--- a/test/orm/backend/test_parameter_binder.cpp
+++ b/test/orm/backend/test_parameter_binder.cpp
@@ -12,8 +12,9 @@ void test_parameter_binder::write_value(size_t /*pos*/, const uint64_t &/*x*/) {
 void test_parameter_binder::write_value(size_t /*pos*/, const bool &/*x*/) {}
 void test_parameter_binder::write_value(size_t /*pos*/, const float &/*x*/) {}
 void test_parameter_binder::write_value(size_t /*pos*/, const double &/*x*/) {}
-void test_parameter_binder::write_value(size_t /*pos*/, const time &/*x*/) {}
-void test_parameter_binder::write_value(size_t /*pos*/, const date &/*x*/) {}
+void test_parameter_binder::write_value(size_t /*pos*/, const utils::date_type_t &/*x*/) {}
+void test_parameter_binder::write_value(size_t /*pos*/, const utils::time_type_t &/*x*/) {}
+void test_parameter_binder::write_value(size_t /*pos*/, const utils::timestamp &/*x*/) {}
 void test_parameter_binder::write_value(size_t /*pos*/, const char * /*x*/) {}
 void test_parameter_binder::write_value(size_t /*pos*/, const char * /*x*/, size_t /*size*/) {}
 void test_parameter_binder::write_value(size_t /*pos*/, const std::string &/*x*/) {}
diff --git a/test/orm/backend/test_parameter_binder.hpp b/test/orm/backend/test_parameter_binder.hpp
index 3110bf7..f3aad26 100644
--- a/test/orm/backend/test_parameter_binder.hpp
+++ b/test/orm/backend/test_parameter_binder.hpp
@@ -18,8 +18,9 @@ public:
   void write_value(size_t pos, const bool &x) override;
   void write_value(size_t pos, const float &x) override;
   void write_value(size_t pos, const double &x) override;
-  void write_value(size_t pos, const time &x) override;
-  void write_value(size_t pos, const date &x) override;
+  void write_value(size_t pos, const utils::date_type_t &x) override;
+  void write_value(size_t pos, const utils::time_type_t &x) override;
+  void write_value(size_t pos, const utils::timestamp &x) override;
   void write_value(size_t pos, const char *x) override;
   void write_value(size_t pos, const char *x, size_t size) override;
   void write_value(size_t pos, const std::string &x) override;