backends/postgres/src/postgres_connection.cpp

@@ -281,7 +281,7 @@ utils::result<std::vector<object::attribute>, utils::error> postgres_connection:
       null_opt = object::null_option_type::NotNull;
     }
     // f.default_value(res->column(4));
-    prototype.emplace_back(name, type, utils::NullAttributes, null_opt);
+    prototype.emplace_back(name, type, utils::null_attributes, null_opt);
   }
 
   return utils::ok(prototype);

demo/object.cpp

@@ -29,7 +29,7 @@ public:
   attribute() = default;
   attribute(std::string name,
             utils::basic_type type,
-            const utils::field_attributes& opts = utils::NullAttributes,
+            const utils::field_attributes& opts = utils::null_attributes,
             null_option_type null_opt = null_option_type::NotNull)
   : name_(std::move(name)), type_(type), options_(opts), null_option_type_(null_opt) {}
 

include/matador/object/attribute.hpp

@@ -28,7 +28,7 @@ public:
   attribute() = default;
   attribute(std::string name,
             utils::basic_type type,
-            const utils::field_attributes &attr = utils::NullAttributes,
+            const utils::field_attributes &attr = utils::null_attributes,
             null_option_type null_opt = null_option_type::NotNull);
 
   [[nodiscard]] const std::string& name() const;
@@ -39,9 +39,9 @@ public:
   [[nodiscard]] bool is_nullable() const;
   [[nodiscard]] utils::basic_type type() const;
   [[nodiscard]] std::shared_ptr<object> owner() const;
-  void change_type(utils::basic_type type, const utils::field_attributes &attr = utils::NullAttributes);
+  void change_type(utils::basic_type type, const utils::field_attributes &attr = utils::null_attributes);
   template < typename Type >
-  void change_type(const utils::field_attributes &attr = utils::NullAttributes) {
+  void change_type(const utils::field_attributes &attr = utils::null_attributes) {
       type_ = utils::data_type_traits<Type>::type(attr.size());
   }
 

include/matador/object/foreign_node_completer.hpp

@@ -39,12 +39,12 @@ public:
   }
 
   template<class PrimaryKeyType>
-  static void on_primary_key(const char * /*id*/, PrimaryKeyType &/*pk*/, const utils::primary_key_attribute & /*attr*/) {}
+  static void on_primary_key(const char * /*id*/, PrimaryKeyType &/*pk*/, const utils::primary_key_attribute & /*attr*/ = utils::default_pk_attributes) {}
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
   template<typename AttributeType>
-  static void on_attribute(const char * /*id*/, AttributeType &/*val*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, AttributeType &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template<typename AttributeType>
-  static void on_attribute(const char * /*id*/, std::optional<AttributeType> &/*val*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, std::optional<AttributeType> &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template<class ForeignPointerType>
   void on_belongs_to(const char *id, ForeignPointerType &/*obj*/, const utils::foreign_attributes &/*attr*/);
   template<class ForeignPointerType>

include/matador/object/join_columns_collector.hpp

@@ -25,10 +25,10 @@ public:
         return join_columns_;
     }
     template < class V >
-    static void on_primary_key(const char * /*id*/, V &, const utils::primary_key_attribute& /*attr*/) {}
+    static void on_primary_key(const char * /*id*/, V &, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {}
     static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
     template<typename Type>
-    static void on_attribute(const char * /*id*/, Type &, const utils::field_attributes &/*attr*/) {}
+    static void on_attribute(const char * /*id*/, Type &, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
     template<class Pointer>
     static void on_belongs_to(const char * /*id*/, Pointer &/*obj*/, const utils::foreign_attributes &/*attr*/) {}
     template<class Pointer>

include/matador/object/object_generator.hpp

@@ -25,13 +25,13 @@ public:
     }
 
     template<typename ValueType>
-    void on_primary_key(const char *, ValueType &/*pk*/, const utils::primary_key_attribute& attr) {
+    void on_primary_key(const char *, ValueType &/*pk*/, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
         type_ = utils::data_type_traits<ValueType>::type(attr.size());
     }
     static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
     template < class Type >
-    static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {}
+    static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
-    static void on_attribute(const char * /*id*/, char * /*x*/, const utils::field_attributes &/*attr*/) {}
+    static void on_attribute(const char * /*id*/, char * /*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
     template<class Pointer>
     static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
     template<class Pointer>
@@ -75,14 +75,14 @@ public:
     }
 
     template < class Type >
-    void on_primary_key(const char *, Type &x, const utils::primary_key_attribute& attr);
+    void on_primary_key(const char *, Type &x, const utils::primary_key_attribute& attr = utils::default_pk_attributes);
     void on_revision(const char *id, uint64_t &rev);
 
     template<typename Type>
-    void on_attribute(const char *id, Type &x, const utils::field_attributes &attr);
+    void on_attribute(const char *id, Type &x, const utils::field_attributes &attr = utils::null_attributes);
 
     template<typename Type>
-    void on_attribute(const char *id, std::optional<Type> &x, const utils::field_attributes &attr);
+    void on_attribute(const char *id, std::optional<Type> &x, const utils::field_attributes &attr = utils::null_attributes);
 
     template<class Pointer>
     void on_belongs_to(const char *id, Pointer &x, const utils::foreign_attributes &/*attr*/) {

include/matador/object/pk_field_locator.hpp

@@ -35,7 +35,7 @@ struct pk_field_locator {
   : base(&obj) {}
 
   template <typename PrimaryKeyType>
-  void on_primary_key(const char *, PrimaryKeyType &pk, const utils::primary_key_attribute & /*attr*/) {
+  void on_primary_key(const char *, PrimaryKeyType &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
     // Offset bestimmen
     const auto* obj_bytes = reinterpret_cast<std::uint8_t*>(base);
     const auto* pk_bytes = reinterpret_cast<std::uint8_t*>(&pk);
@@ -113,7 +113,7 @@ struct pk_field_locator {
   }
   static void on_revision(const char *, std::uint64_t &) {}
   template <typename V>
-  static void on_attribute(const char *, V &, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char *, V &, const utils::field_attributes & = matador::utils::null_attributes) {}
   template <typename Pointer>
   static void on_belongs_to(const char *, Pointer &, const utils::foreign_attributes &) {}
   template <typename Pointer>

include/matador/object/primary_key_resolver.hpp

@@ -44,7 +44,7 @@ public:
   }
 
   template < class Type >
-  void on_primary_key(const char *id, Type &pk, const utils::primary_key_attribute& attr) {
+  void on_primary_key(const char *id, Type &pk, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
     primary_key_info_.pk_column_name = id;
     primary_key_info_.type = utils::data_type_traits<Type>::type(attr.size());
     primary_key_info_.pk = pk;
@@ -52,7 +52,7 @@ public:
 
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
   template<typename Type>
-  static void on_attribute(const char * /*id*/, Type &/*val*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, Type &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template<class Pointer>
   static void on_belongs_to(const char * /*id*/, Pointer &/*val*/, const utils::foreign_attributes &/*attr*/) {}
   template<class Pointer>

include/matador/object/relation_completer.hpp

@@ -29,12 +29,12 @@ public:
     }
 
     template<class PrimaryKeyType>
-    static void on_primary_key(const char * /*id*/, PrimaryKeyType &/*pk*/, const utils::primary_key_attribute& /*attr*/) {}
+    static void on_primary_key(const char * /*id*/, PrimaryKeyType &/*pk*/, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {}
     static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
     template<typename AttributeType>
-    static void on_attribute(const char * /*id*/, AttributeType &/*val*/, const utils::field_attributes &/*attr*/) {}
+    static void on_attribute(const char * /*id*/, AttributeType &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
     template<typename AttributeType>
-    static void on_attribute(const char * /*id*/, std::optional<AttributeType> &/*val*/, const utils::field_attributes &/*attr*/) {}
+    static void on_attribute(const char * /*id*/, std::optional<AttributeType> &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
 
     template<class ForeignPointerType>
     void on_belongs_to(const char *id, ForeignPointerType &/*obj*/, const utils::foreign_attributes &/*attr*/) {
@@ -103,12 +103,12 @@ public:
   }
 
   template<class PrimaryKeyType>
-  static void on_primary_key(const char * /*id*/, PrimaryKeyType &/*pk*/, const utils::primary_key_attribute& /*attr*/) {}
+  static void on_primary_key(const char * /*id*/, PrimaryKeyType &/*pk*/, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {}
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
   template<typename AttributeType>
-  static void on_attribute(const char * /*id*/, AttributeType &/*val*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, AttributeType &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template<typename AttributeType>
-  static void on_attribute(const char * /*id*/, std::optional<AttributeType> &/*val*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, std::optional<AttributeType> &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
 
   template<class ForeignPointerType>
   void on_belongs_to(const char *id, ForeignPointerType &obj, const utils::foreign_attributes &attr);

include/matador/orm/session.hpp

@@ -179,7 +179,7 @@ public:
   }
 
   template<class Type>
-  void on_primary_key(const char * /*id*/, Type &x, const utils::primary_key_attribute & /*attr*/) {
+  void on_primary_key(const char * /*id*/, Type &x, const utils::primary_key_attribute & /*attr*/ = utils::default_pk_attributes) {
     stmt_.bind(binding_position_, x);
   }
 
@@ -187,17 +187,17 @@ public:
   }
 
   template<class Type>
-  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template<class Pointer>
-  static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
+  static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
   template<class Pointer>
-  static void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
+  static void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
 
   template<class ContainerType>
   static void on_has_many(const char * /*id*/,
                           ContainerType &/*c*/,
                           const char * /*join_column*/,
-                          const utils::foreign_attributes &/*attr*/) {}
+                          const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
 
   template<class ContainerType>
   static void on_has_many_to_many(const char * /*id*/,

include/matador/query/basic_schema.hpp

@@ -41,12 +41,12 @@ public:
     return generator_type_;
   }
   template<class V>
-  void on_primary_key(const char * /*id*/, V &/*pk*/, const utils::primary_key_attribute &attr) {
+  void on_primary_key(const char * /*id*/, V &/*pk*/, const utils::primary_key_attribute &attr = utils::default_pk_attributes) {
     generator_type_ = attr.generator();
   }
   static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
   template<typename T>
-  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
   template<class P>
   static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
   template<class P>

include/matador/query/dependency_collector.hpp

@@ -60,15 +60,15 @@ struct dependency_collector {
   std::vector<fk_ref> refs;
 
   template<class V>
-  static void on_primary_key(const char*, V&, const utils::primary_key_attribute& /*attr*/) {}
+  static void on_primary_key(const char*, V&, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {}
 
   static void on_revision(const char*, std::uint64_t&) {}
 
   template<class V>
-  static void on_attribute(const char*, V&, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char*, V&, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
 
   template<class Pointer>
-  void on_belongs_to(const char* id, Pointer& p, utils::foreign_attributes &/*attr*/) {
+  void on_belongs_to(const char* id, Pointer& p, utils::foreign_attributes &attr) {
     // Erwartung: Pointer verhält sich wie matador::object::object_ptr<T>
     // also: p.get() liefert raw ptr, und Pointer::value_type / element_type ist T.
     auto* raw = p.get();

include/matador/query/fk_value_extractor.hpp

@@ -25,13 +25,13 @@ public:
   }
 
   template<typename ValueType>
-  void on_primary_key(const char *, ValueType &pk, const utils::primary_key_attribute& /*attr*/) {
+  void on_primary_key(const char *, ValueType &pk, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {
     value_ = pk;
   }
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
   template < class Type >
-  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
-  static void on_attribute(const char * /*id*/, char * /*x*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, char * /*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template<class Pointer>
   static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
   template<class Pointer>

include/matador/query/generator.hpp

@@ -64,13 +64,13 @@ public:
   }
 
   template < class V >
-  void on_primary_key(const char *id, V &, const utils::primary_key_attribute& /*attr*/) {
+  void on_primary_key(const char *id, V &, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {
       push(id);
   }
   void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  void on_attribute(const char *id, Type &, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char *id, Type &, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
       push(id);
   }
 
@@ -105,7 +105,7 @@ public:
   }
 
   template<class CollectionType>
-  void on_has_many(const char * /*id*/, CollectionType &, const char * /*join_column*/, const utils::foreign_attributes &/*attr*/, std::enable_if_t<!object::is_object_ptr<typename CollectionType::value_type>::value> * = nullptr) {
+  void on_has_many(const char * /*id*/, CollectionType &, const char *join_column, const utils::foreign_attributes &attr, std::enable_if_t<!object::is_object_ptr<typename CollectionType::value_type>::value> * = nullptr) {
   }
 
   template<class ContainerType>
@@ -170,13 +170,13 @@ public:
   }
 
   template < class V >
-  void on_primary_key(const char * /*id*/, V &/*x*/, const utils::primary_key_attribute& /*attr*/) {
+  void on_primary_key(const char * /*id*/, V &/*x*/, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {
     result_.emplace_back(utils::_);
   }
   void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     result_.emplace_back(utils::_);
   }
 
@@ -228,13 +228,13 @@ public:
   }
 
   template < class V >
-  void on_primary_key(const char *id, V &x, const utils::primary_key_attribute& /*attr*/) {
+  void on_primary_key(const char *id, V &x, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {
     push_back(id, x);
   }
   void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  void on_attribute(const char *id, Type &x, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char *id, Type &x, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     push_back(id, x);
   }
 

include/matador/query/insert_query_builder.hpp

@@ -6,9 +6,81 @@
 #include "matador/query/query.hpp"
 #include "matador/query/query_builder_exception.hpp"
 
-#include "matador/utils/primary_key_accessor.hpp"
-
 namespace matador::query {
+
+struct pk_setter {
+  const std::string &name;
+  std::uint64_t value;
+
+  template<class V>
+  void on_primary_key(const char *id, V &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
+    if (id != nullptr && name == id) {
+      pk = static_cast<V>(value);
+    }
+  }
+  static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
+  template<typename T>
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
+  template<class P>
+  static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class P>
+  static void on_has_one(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const utils::foreign_attributes & ) {}
+};
+
+struct pk_unset_checker {
+  const std::string &name;
+  bool unset{true};
+
+  template<class V>
+  void on_primary_key(const char *id, V &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
+    if (id != nullptr && name == id) {
+      // Your convention: 0 means unset for integer PKs
+      unset = (static_cast<std::uint64_t>(pk) == 0ULL);
+    }
+  }
+  static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
+  template<typename T>
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
+  template<class P>
+  static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class P>
+  static void on_has_one(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const utils::foreign_attributes & ) {}
+};
+
+struct pk_value_extractor {
+  std::uint64_t value{0};
+
+  template<class V>
+  void on_primary_key(const char * /*id*/, V &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
+    value = static_cast<std::uint64_t>(pk);
+  }
+  static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
+  template<typename T>
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
+  template<class P>
+  static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class P>
+  static void on_has_one(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const utils::foreign_attributes & ) {}
+};
+
 class insert_query_builder {
 public:
   using step_query_t = std::variant<executable_query, fetchable_query>;
@@ -18,7 +90,10 @@ public:
 
     // Session uses these to handle manual/sequence/table pre-insert PKs
     utils::generator_type pk_generator{utils::generator_type::Manual};
-    utils::primary_key_accessor pk_accessor;
+    std::string pk_name;
+
+    std::function<bool()> pk_is_unset{};
+    std::function<void(std::uint64_t)> set_pk{};
 
     // Identity post-insert
     std::function<void(const sql::record &)> apply_returning{};
@@ -48,11 +123,11 @@ public:
   }
 
   template < class V >
-  static void on_primary_key(const char * /*id*/, V &, const utils::primary_key_attribute& /*attr*/) {}
+  static void on_primary_key(const char * /*id*/, V &, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {}
   static void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  static void on_attribute(const char * /*id*/, Type &, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, Type &, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
 
   template<class Pointer>
   void on_belongs_to(const char * /*id*/, Pointer &obj, const utils::foreign_attributes &attr) {
@@ -63,19 +138,8 @@ public:
   void on_has_one(const char * /*id*/, Pointer &obj, const utils::foreign_attributes &attr) {
     on_foreign_object(obj, attr);
   }
-  template<class CollectionType>
+  template<class Collection>
-  void on_has_many(const char * /*id*/, CollectionType &con, const char *, const utils::foreign_attributes &attr, std::enable_if_t<object::is_object_ptr<typename CollectionType::value_type>::value> * = nullptr) {
+  static void on_has_many(const char * /*id*/, Collection &/*con*/, const char * /*join_column*/, const utils::foreign_attributes & ) {}
-    if (!utils::is_cascade_type_set(attr.cascade(), utils::cascade_type::Insert)) {
-      return;
-    }
-    for (auto &obj : con) {
-      obj.is_persistent() ? build_for(obj) : on_foreign_object(obj, attr);
-
-    }
-
-  }
-  template<class CollectionType>
-  void on_has_many(const char * /*id*/, CollectionType &/*con*/, const char *, const utils::foreign_attributes &/*attr*/, std::enable_if_t<!object::is_object_ptr<typename CollectionType::value_type>::value> * = nullptr) {}
   template<class Collection>
   void on_has_many_to_many(const char *id, Collection &container, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes & ) {
     if (id == nullptr || join_column == nullptr || inverse_join_column == nullptr) {
@@ -105,18 +169,19 @@ public:
       }
 
       // Extract FK value from the foreign object
-      insert_step rel_step{};
+      pk_value_extractor fk{};
-      const auto pk = rel_step.pk_accessor.get(obj);
+      access::process(fk, *obj);
-      if (pk.is_valid()) {
+      if (fk.value == 0ULL) {
         continue;
       }
 
       // Build INSERT into relation table with the 2 FK columns
-      // rel_step.query = executable_query{
+      insert_step rel_step{};
-        // insert()
+      rel_step.query = executable_query{
-          // .into(relation_table, {table_column{&relation_table, join_column}, table_column{&relation_table, inverse_join_column}})
+        insert()
-          // .values({utils::database_type{current_entity_pk_}, utils::database_type{fk.value}})
+          .into(relation_table, {table_column{&relation_table, join_column}, table_column{&relation_table, inverse_join_column}})
-      // };
+          .values({utils::database_type{current_entity_pk_}, utils::database_type{fk.value}})
+      };
       relation_steps_.push_back(std::move(rel_step));
     }
   }
@@ -162,18 +227,29 @@ private:
     const auto &info = it->second.node().info();
     insert_step step{};
     if (info.has_primary_key()) {
+      step.pk_name = info.primary_key_attribute()->name();
       step.pk_generator = it->second.pk_generator().type();
+
+      step.pk_is_unset = [ptr, name = step.pk_name]() {
+        pk_unset_checker chk{name};
+        access::process(chk, *ptr);
+        return chk.unset;
+      };
+
+      step.set_pk = [ptr, name = step.pk_name](std::uint64_t v) {
+        pk_setter setter{name, v};
+        access::process(setter, *ptr);
+      };
     }
 
     if (info.has_primary_key() && step.pk_generator == utils::generator_type::Identity) {
-      const auto pk_name = info.primary_key_attribute()->name();
+      const table_column pk_col(&it->second.table(), step.pk_name);
-      const table_column pk_col(&it->second.table(), pk_name);
       step.query = fetchable_query{insert().into(it->second.table()).values(*ptr).returning(pk_col)};
-      step.apply_returning = [ptr, &step, pk_name = pk_name](const sql::record &rec) {
+      step.apply_returning = [ptr, pk_name = step.pk_name](const sql::record &rec) {
-        const auto& f = rec.at(pk_name);
+        if (auto v = rec.at<std::uint64_t>(pk_name); v.has_value()) {
-        utils::identifier id;
+          pk_setter setter{pk_name, *v};
-        id.assign(f.value());
+          access::process(setter, *ptr);
-        step.pk_accessor.set(*ptr, id);
+        }
       };
     } else {
       step.query = executable_query{insert().into(it->second.table()).values(*ptr)};
@@ -202,7 +278,6 @@ private:
   std::vector<insert_step> relation_steps_;
   std::unordered_set<std::pair<std::type_index, const void *>, visit_key_hash> visited_;
 
-
   std::uint64_t current_entity_pk_{0};
 };
 }

include/matador/query/key_value_generator.hpp

@@ -27,13 +27,13 @@ public:
   }
 
   template < class V >
-  void on_primary_key(const char *id, V &x, const utils::primary_key_attribute& /*attr*/) {
+  void on_primary_key(const char *id, V &x, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {
     result_.emplace_back(id, x);
   }
   void on_revision(const char *id, uint64_t &/*rev*/) const;
 
   template<typename Type>
-  void on_attribute(const char *id, Type &x, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char *id, Type &x, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     result_.emplace_back(id, x);
   }
 

include/matador/query/schema.hpp

@@ -61,10 +61,10 @@ public:
   {}
 
   template<typename ValueType>
-  static void on_primary_key(const char * /*id*/, ValueType &/*value*/, const utils::primary_key_attribute& /*attr*/) {}
+  static void on_primary_key(const char * /*id*/, ValueType &/*value*/, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {}
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
   template<class Type>
-  static void on_attribute(const char * /*id*/, Type &/*value*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, Type &/*value*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template<class Pointer>
   static void on_belongs_to(const char * /*id*/, Pointer & /*x*/, const utils::foreign_attributes &/*attr*/) {}
   template<class Pointer>

include/matador/query/select_query_builder.hpp

@@ -90,7 +90,7 @@ public:
   }
 
   template < class V >
-  void on_primary_key(const char *id, V &, const utils::primary_key_attribute& /*attr*/) {
+  void on_primary_key(const char *id, V &, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {
     push(id);
     if (!is_root_entity()) {
       return;
@@ -101,7 +101,7 @@ public:
   void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  void on_attribute(const char *id, Type &, const utils::field_attributes &/*attr*/)
+  void on_attribute(const char *id, Type &, const utils::field_attributes &/*attr*/ = utils::null_attributes)
   {
     push(id);
   }

include/matador/query/value_extractor.hpp

@@ -26,16 +26,16 @@ public:
   }
 
   template<typename ValueType>
-  void on_primary_key(const char *, ValueType &x, const utils::primary_key_attribute& attr) {
+  void on_primary_key(const char *, ValueType &x, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
     utils::data_type_traits<ValueType>::bind_value(*this, 0, x, attr.size());
   }
   void on_revision(const char *id, uint64_t &rev);
   template < class Type >
-  void on_attribute(const char *, Type &x, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char *, Type &x, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     utils::data_type_traits<Type>::bind_value(*this, 0, x);
   }
-  void on_attribute(const char *id, char *x, const utils::field_attributes &/*attr*/);
+  void on_attribute(const char *id, char *x, const utils::field_attributes &/*attr*/ = utils::null_attributes);
-  void on_attribute(const char *id, std::string &x, const utils::field_attributes &/*attr*/);
+  void on_attribute(const char *id, std::string &x, const utils::field_attributes &/*attr*/ = utils::null_attributes);
 
   template<class Type, template < class ... > class Pointer>
   void on_belongs_to(const char * /*id*/, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/) {

include/matador/sql/field.hpp

@@ -42,7 +42,6 @@ public:
   [[nodiscard]] utils::constraints type() const;
   [[nodiscard]] size_t size() const;
   [[nodiscard]] int index() const;
-  [[nodiscard]] utils::value value() const;
 
   template<class Type>
   std::optional<Type> as() const {

include/matador/sql/generator.hpp

@@ -45,7 +45,7 @@ public:
   }
 
   template < class V >
-  void on_primary_key(const char *id, V &, const utils::primary_key_attribute& /*attr*/) {
+  void on_primary_key(const char *id, V &, const utils::primary_key_attribute& /*attr*/ = utils::default_pk_attributes) {
       if (has_many_to_many_) {
           return;
       }
@@ -54,7 +54,7 @@ public:
   void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  void on_attribute(const char *id, Type &, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char *id, Type &, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
       if (has_many_to_many_) {
           return;
       }

include/matador/sql/internal/identifier_reader.hpp

@@ -23,14 +23,14 @@ public:
   }
 
   template<typename ValueType>
-  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr) {
+  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
     utils::data_type_traits<ValueType>::read_value(reader_, id, column_index_, value, attr.size());
     identifier_ = value;
   }
 
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
   template < class Type >
-  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template < class Pointer >
   static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
   template < class Pointer >

include/matador/sql/internal/object_result_binder.hpp

@@ -28,21 +28,21 @@ public:
   }
 
   template<typename ValueType>
-  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr);
+  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr = utils::default_pk_attributes);
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
 
   template < class Type >
-  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {}
+  static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
   template < class Pointer >
-  static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
+  static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
   template < class Pointer >
-  static void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
+  static void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
 
   template<class ContainerType>
   static void on_has_many(const char * /*id*/,
                           ContainerType &/*c*/,
                           const char * /*join_column*/,
-                          const utils::foreign_attributes &/*attr*/) {}
+                          const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
   template<class ContainerType>
   static void on_has_many_to_many(const char * /*id*/,
                                   ContainerType &/*c*/,
@@ -74,32 +74,32 @@ public:
   void reset();
 
   template < class Type >
-  void on_primary_key(const char *id, Type &val, const utils::primary_key_attribute& attr) {
+  void on_primary_key(const char *id, Type &val, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
     utils::data_type_traits<Type>::read_value(*binder_, id, index_++, val, attr.size());
   }
   void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  void on_attribute(const char *id, Type &val, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char *id, Type &val, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     utils::data_type_traits<Type>::read_value(*binder_, id, index_++, val);
   }
-  void on_attribute(const char *id, char *value, const utils::field_attributes &attr);
+  void on_attribute(const char *id, char *value, const utils::field_attributes &attr = utils::null_attributes);
-  void on_attribute(const char *id, std::string &value, const utils::field_attributes &attr);
+  void on_attribute(const char *id, std::string &value, const utils::field_attributes &attr = utils::null_attributes);
-  void on_attribute(const char *id, utils::value &val, const utils::field_attributes &attr);
+  void on_attribute(const char *id, utils::value &val, const utils::field_attributes &attr = utils::null_attributes);
 
   template<class Type, template < class ... > class Pointer>
-  void on_belongs_to(const char *id, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/) {
+  void on_belongs_to(const char *id, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {
     fk_result_binder_.bind(*x, id, index_++, *binder_);
   }
   template<class Type, template < class ... > class Pointer>
-  void on_has_one(const char *id, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/) {
+  void on_has_one(const char *id, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {
     fk_result_binder_.bind(*x, id, index_++, *binder_);
   }
   template<class ContainerType>
   static void on_has_many(const char * /*id*/,
                           ContainerType &/*c*/,
                           const char * /*join_column*/,
-                          const utils::foreign_attributes &/*attr*/) {}
+                          const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
   template<class ContainerType>
   static void on_has_many_to_many(const char * /*id*/,
                                   ContainerType &/*c*/,

include/matador/sql/internal/pk_reader.hpp

@@ -15,13 +15,13 @@ public:
   }
 
   template<typename ValueType>
-  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr);
+  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr = utils::default_pk_attributes);
   void on_revision(const char * /*id*/, uint64_t &/*rev*/) {
     ++column_index_;
   }
 
   template<class Type>
-  void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     ++column_index_;
   }
 

include/matador/sql/internal/query_result_impl.hpp

@@ -41,7 +41,7 @@ public:
                     size_t column_index = 0);
 
   template<typename ValueType>
-  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr) {
+  void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
     utils::data_type_traits<ValueType>::read_value(*reader_, id, column_index_++, value, attr.size());
     if (type_stack_.size() == 1) {
       last_pk_ = current_pk_;
@@ -52,13 +52,13 @@ public:
   void on_revision(const char *id, uint64_t &rev);
 
   template<class Type>
-  void on_attribute(const char *id, Type &x, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char *id, Type &x, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     utils::data_type_traits<Type>::read_value(*reader_, id, column_index_++, x);
   }
 
-  void on_attribute(const char *id, char *value, const utils::field_attributes &attr);
+  void on_attribute(const char *id, char *value, const utils::field_attributes &attr = utils::null_attributes);
-  void on_attribute(const char *id, std::string &value, const utils::field_attributes &attr);
+  void on_attribute(const char *id, std::string &value, const utils::field_attributes &attr = utils::null_attributes);
-  void on_attribute(const char *id, utils::value &val, const utils::field_attributes &attr);
+  void on_attribute(const char *id, utils::value &val, const utils::field_attributes &attr = utils::null_attributes);
 
   template<class Pointer>
   void on_belongs_to(const char * /*id*/, Pointer &x, const utils::foreign_attributes &attr) {

include/matador/sql/internal/query_result_pk_resolver.hpp

@@ -28,7 +28,7 @@ public:
     }
 
     template<typename ValueType>
-    void on_primary_key(const char *id, ValueType &/*value*/, const utils::primary_key_attribute& attr) {
+    void on_primary_key(const char *id, ValueType &/*value*/, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
         if (!type_stack_.empty()) {
             return;
         }
@@ -39,8 +39,8 @@ public:
     void on_revision(const char * /*id*/, uint64_t &/*rev*/) { ++column_index_; }
 
     template < class Type >
-    void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) { ++column_index_; }
+    void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) { ++column_index_; }
-    void on_attribute(const char *id, const utils::value &x, const utils::field_attributes &attr);
+    void on_attribute(const char *id, const utils::value &x, const utils::field_attributes &attr = utils::null_attributes);
 
     template < class Pointer >
     void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &attr) { on_foreign_key<typename Pointer::value_type>(attr.fetch() ); }

include/matador/sql/object_parameter_binder.hpp

@@ -18,29 +18,29 @@ public:
   [[nodiscard]] size_t current_index() const;
 
   template < class Type >
-  void on_primary_key(const char * /*id*/, Type &val, const utils::primary_key_attribute& attr) {
+  void on_primary_key(const char * /*id*/, Type &val, const utils::primary_key_attribute& attr = utils::default_pk_attributes) {
     utils::data_type_traits<Type>::bind_value(*binder_, index_++, val, attr.size());
   }
   void on_revision(const char *id, uint64_t &/*rev*/);
 
   template<typename Type>
-  void on_attribute(const char * /*id*/, Type &val, const utils::field_attributes &/*attr*/) {
+  void on_attribute(const char * /*id*/, Type &val, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
     utils::data_type_traits<Type>::bind_value(*binder_, index_++, val);
   }
 
   template<class Type, template < class ... > class Pointer>
-  void on_belongs_to(const char * /*id*/, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/) {
+  void on_belongs_to(const char * /*id*/, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {
     pk_binder_.bind(*x, index_++, *binder_);
   }
   template<class Type, template < class ... > class Pointer>
-  void on_has_one(const char * /*id*/, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/) {
+  void on_has_one(const char * /*id*/, Pointer<Type> &x, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {
     pk_binder_.bind(*x, index_++, *binder_);
   }
   template<class ContainerType>
   static void on_has_many(const char * /*id*/,
                           ContainerType &/*c*/,
                           const char * /*join_column*/,
-                          const utils::foreign_attributes &/*attr*/) {}
+                          const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
   template<class ContainerType>
   static void on_has_many_to_many(const char * /*id*/,
                                   ContainerType &/*c*/,

include/matador/sql/object_pk_binder.hpp

@@ -20,21 +20,21 @@ public:
     }
 
     template<typename ValueType>
-    void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr);
+    void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr = utils::default_pk_attributes);
     static void on_revision(const char * /*id*/, unsigned long long &/*rev*/) {}
 
     template < class Type >
-    static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/) {}
+    static void on_attribute(const char * /*id*/, Type &/*x*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
     template < class Pointer >
-    static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
+    static void on_belongs_to(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
     template < class Pointer >
-    static void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
+    static void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
 
     template<class ContainerType>
     static void on_has_many(const char * /*id*/,
                             ContainerType &/*c*/,
                             const char * /*join_column*/,
-                            const utils::foreign_attributes &/*attr*/) {}
+                            const utils::foreign_attributes &/*attr*/ = utils::CascadeNoneFetchLazy) {}
     template<class ContainerType>
     static void on_has_many_to_many(const char * /*id*/,
                                     ContainerType &/*c*/,

include/matador/utils/access.hpp

@@ -1,10 +1,7 @@
 #ifndef OOS_ACCESS_HPP
 #define OOS_ACCESS_HPP
 
-#include "matador/utils/primary_key_attribute.hpp"
+#include <cstdint>
-#include "matador/utils/field_attributes.hpp"
-#include "matador/utils/foreign_attributes.hpp"
-
 #include <optional>
 
 namespace matador {
@@ -32,66 +29,108 @@ template<class Base, class Derived, class Operator>
 void process_base(Operator &op, const Derived &object) {
   static_assert(!std::is_same_v<Base, Derived>, "class Base must not be of same type as class Derived");
   static_assert(std::is_base_of_v<Base, Derived>, "class Base must be base of class Derived");
-  op.on_base(static_cast<const Base&>(object));
+  process(op, static_cast<const Base&>(object));
 }
 
 template<class Base, class Derived, class Operator>
 void process_base(Operator &op, Derived &object) {
   static_assert(!std::is_same_v<Base, Derived>, "class Base must not be of same type as class Derived");
   static_assert(std::is_base_of_v<Base, Derived>, "class Base must be base of class Derived");
-  op.on_base(static_cast<Base&>(object));
+  process(op, static_cast<Base&>(object));
 }
 
 template< class Operator, class Type >
-void primary_key(Operator &op, const char *id, Type &value, const utils::primary_key_attribute &attr = utils::DefaultPkAttributes) {
+void primary_key(Operator &op, const char *id, Type &value, const utils::primary_key_attribute &attr) {
   op.on_primary_key(id, value, attr);
 }
 
+template< class Operator, class Type >
+void primary_key(Operator &op, const char *id, Type &value) {
+  op.on_primary_key(id, value);
+}
+
 template<class Operator>
 void revision(Operator &op, const char *id, uint64_t &value) {
   op.on_revision(id, value);
 }
 
 template<class Operator, class Type>
-void attribute(Operator &op, const char *id, Type &value, const utils::field_attributes &attr = utils::NullAttributes) {
+void attribute(Operator &op, const char *id, Type &value, const utils::field_attributes &attr) {
   op.on_attribute(id, value, attr);
 }
 
 template<class Operator, class Type>
-void attribute(Operator &op, const char *id, std::optional<Type> &value, const utils::field_attributes &attr = utils::NullAttributes) {
+void attribute(Operator &op, const char *id, std::optional<Type> &value, const utils::field_attributes &attr) {
   op.on_attribute(id, value, attr);
 }
 
 template<class Operator, class Type>
-void has_one(Operator &op, const char *id, Type &value, const utils::foreign_attributes &attr = utils::CascadeNoneFetchLazy) {
+void attribute(Operator &op, const char *id, Type &value) {
+  op.on_attribute(id, value);
+}
+
+template<class Operator, class Type>
+void has_one(Operator &op, const char *id, Type &value, const utils::foreign_attributes &attr) {
   op.on_has_one(id, value, attr);
 }
 
 template<class Operator, class Type>
-void belongs_to(Operator &op, const char *id, Type &value, const utils::foreign_attributes &attr = utils::CascadeNoneFetchLazy) {
+void has_one(Operator &op, const char *id, Type &value) {
+  op.on_has_one(id, value);
+}
+
+template<class Operator, class Type>
+void belongs_to(Operator &op, const char *id, Type &value, const utils::foreign_attributes &attr) {
   op.on_belongs_to(id, value, attr);
 }
 
+template<class Operator, class Type>
+void belongs_to(Operator &op, const char *id, Type &value) {
+  op.on_belongs_to(id, value);
+}
+
 template<class Operator, class Type, template<class ...> class ContainerType>
-void has_many(Operator &op, const char *id, ContainerType<Type> &c, const char *join_column, const utils::foreign_attributes &attr = utils::CascadeNoneFetchLazy) {
+void has_many(Operator &op, const char *id, ContainerType<Type> &c, const char *join_column, const utils::foreign_attributes &attr) {
   op.on_has_many(id, c, join_column, attr);
 }
 
 template<class Operator, class Type, template<class ...> class ContainerType>
-void has_many(Operator &op, const char *id, ContainerType<Type> &c, const utils::foreign_attributes &attr = utils::CascadeNoneFetchLazy) {
+void has_many(Operator &op, const char *id, ContainerType<Type> &c, const char *join_column) {
+  op.on_has_many(id, c, join_column);
+}
+
+template<class Operator, class Type, template<class ...> class ContainerType>
+void has_many(Operator &op, const char *id, ContainerType<Type> &c, const utils::foreign_attributes &attr) {
   op.on_has_many(id, c, attr);
 }
 
+template<class Operator, class Type, template<class ...> class ContainerType>
+void has_many(Operator &op, const char *id, ContainerType<Type> &c) {
+  op.on_has_many(id, c);
+}
+
 template<class Operator, class ContainerType>
-void has_many_to_many(Operator &op, const char *id, ContainerType &c, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes &attr = utils::CascadeNoneFetchLazy) {
+void has_many_to_many(Operator &op, const char *id, ContainerType &c, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes &attr) {
   op.on_has_many_to_many(id, c, join_column, inverse_join_column, attr);
 }
 
 template<class Operator, class ContainerType>
-void has_many_to_many(Operator &op, const char *id, ContainerType &c, const utils::foreign_attributes &attr = utils::CascadeNoneFetchLazy) {
+void has_many_to_many(Operator &op, const char *id, ContainerType &c, const char *join_column, const char *inverse_join_column) {
+  op.on_has_many_to_many(id, c, join_column, inverse_join_column);
+}
+
+template<class Operator, class ContainerType>
+void has_many_to_many(Operator &op, const char *id, ContainerType &c, const utils::foreign_attributes &attr) {
   op.on_has_many_to_many(id, c, attr);
 }
+
+template<class Operator, class ContainerType>
+void has_many_to_many(Operator &op, const char *id, ContainerType &c) {
+  op.on_has_many_to_many(id, c);
 }
+
+}
+
 }
 
 #endif //OOS_ACCESS_HPP

include/matador/utils/errors.hpp

@@ -9,7 +9,6 @@ namespace matador::utils {
 
 enum class utils_error {
   InvalidVersionString,
-  IdentifierTypeMismatch
 };
 
 class utils_category_impl final : public std::error_category

include/matador/utils/field_attributes.hpp

@@ -74,7 +74,7 @@ private:
   constraints options_ = constraints::None;
 };
 
-const field_attributes NullAttributes {};
+const field_attributes null_attributes {};
 
 }
 #endif //MATADOR_FIELD_ATTRIBUTES_HPP

include/matador/utils/identifier.hpp

@@ -1,22 +1,16 @@
 #ifndef MATADOR_IDENTIFIER_HPP
 #define MATADOR_IDENTIFIER_HPP
 
-#include "matador/utils/basic_types.hpp"
 #include "matador/utils/default_type_traits.hpp"
-#include "matador/utils/error.hpp"
 #include "matador/utils/field_attributes.hpp"
-#include "matador/utils/result.hpp"
+#include "matador/utils/basic_types.hpp"
 #include "matador/utils/types.hpp"
 
 #include <memory>
-#include <ostream>
 #include <string>
-#include <type_traits>
 #include <typeindex>
-#include <variant>
 
 namespace matador::utils {
-class value;
 class identifier_serializer {
 public:
   virtual ~identifier_serializer() = default;
@@ -37,13 +31,7 @@ template<typename Type, class Enabled = void>
 struct identifier_type_traits;
 
 template<typename Type>
-struct identifier_type_traits<Type, std::enable_if_t<std::is_integral_v<Type> && std::is_signed_v<Type> > > {
+struct identifier_type_traits<Type, std::enable_if_t<std::is_integral_v<Type> > > {
-  static bool is_valid(Type value) { return value != 0; }
-  static std::string to_string(const Type value) { return std::to_string(value); }
-};
-
-template<typename Type>
-struct identifier_type_traits<Type, std::enable_if_t<std::is_integral_v<Type> && !std::is_signed_v<Type> > > {
   static bool is_valid(Type value) { return value > 0; }
   static std::string to_string(const Type value) { return std::to_string(value); }
 };
@@ -60,77 +48,127 @@ struct identifier_type_traits<null_type_t, void> {
   static std::string to_string() { return "null"; }
 };
 
+template<>
+struct identifier_type_traits<const char *, void> {
+  static bool is_valid(const char *value);
+  static std::string to_string(const char *value);
+};
+
 namespace detail {
 template<typename Type>
 size_t hash(const Type &value) {
   return std::hash<Type>()(value);
 }
 
-size_t hash(const std::string &value);
+size_t hash(const char *value);
 }
 
-template <class T>
-struct is_identifier_supported : std::false_type {};
-
-template <> struct is_identifier_supported<int8_t> : std::true_type {};
-template <> struct is_identifier_supported<int16_t> : std::true_type {};
-template <> struct is_identifier_supported<int32_t> : std::true_type {};
-template <> struct is_identifier_supported<int64_t> : std::true_type {};
-template <> struct is_identifier_supported<uint8_t> : std::true_type {};
-template <> struct is_identifier_supported<uint16_t> : std::true_type {};
-template <> struct is_identifier_supported<uint32_t> : std::true_type {};
-template <> struct is_identifier_supported<uint64_t> : std::true_type {};
-template <> struct is_identifier_supported<std::string> : std::true_type {};
-
-template <class T>
-inline constexpr bool is_identifier_supported_v = is_identifier_supported<std::decay_t<T>>::value;
-
 class identifier {
-public:
+private:
-  using value_type = std::variant<
+  struct base {
-    std::monostate,
+    base(const std::type_index &ti, basic_type type);
-    int8_t, int16_t, int32_t, int64_t,
+    base(const base &x) = delete;
-    uint8_t, uint16_t, uint32_t, uint64_t,
+    base &operator=(const base &x) = delete;
-    std::string
+    base(base &&x) = delete;
-  >;
+    base &operator=(base &&x) = delete;
+    virtual ~base() = default;
 
-  identifier();
+    [[nodiscard]] virtual base *copy() const = 0;
-  template<typename Type, std::enable_if_t<is_identifier_supported_v<Type>, int> = 0>
+    [[nodiscard]] virtual bool equal_to(const base &x) const = 0;
-  explicit identifier(Type &&id)
+    [[nodiscard]] virtual bool less(const base &x) const = 0;
-  : value_(std::forward<Type>(id)) {
+    [[nodiscard]] virtual bool is_valid() const = 0;
+    virtual void serialize(identifier_serializer &s) = 0;
+    [[nodiscard]] virtual std::string str() const = 0;
+    [[nodiscard]] virtual size_t hash() const = 0;
+
+    std::type_index type_index_;
+    basic_type type_{basic_type::Null};
+  };
+
+  template<class IdType>
+  struct pk final : base {
+    using self = pk;
+
+    explicit pk(const IdType &id)
+    : base(std::type_index(typeid(IdType)), data_type_traits<IdType>::type(1))
+      , id_(id)
+      , size_(sizeof(IdType)) {
     }
 
-  identifier(const identifier &x) = default;
+    [[nodiscard]] base *copy() const override {
+      return new self(id_);
+    }
+
+    [[nodiscard]] bool equal_to(const base &x) const override {
+      return static_cast<const pk &>(x).id_ == id_;
+    }
+
+    [[nodiscard]] bool less(const base &x) const override {
+      return id_ < static_cast<const pk &>(x).id_;
+    }
+
+    [[nodiscard]] bool is_valid() const override {
+      return identifier_type_traits<IdType>::is_valid(id_);
+    }
+
+    [[nodiscard]] std::string str() const override {
+      return identifier_type_traits<IdType>::to_string(id_);
+    }
+
+    void serialize(identifier_serializer &s) override {
+      s.serialize(id_, size_);
+    }
+
+    [[nodiscard]] size_t hash() const override {
+      return detail::hash(id_);
+    }
+
+    IdType id_;
+    size_t size_{};
+  };
+
+  struct null_pk final : base {
+    null_pk();
+    [[nodiscard]] base *copy() const override;
+    [[nodiscard]] bool equal_to(const base &x) const override;
+    [[nodiscard]] bool less(const base &x) const override;
+    [[nodiscard]] bool is_valid() const override;
+    void serialize(identifier_serializer &s) override;
+    [[nodiscard]] std::string str() const override;
+    [[nodiscard]] size_t hash() const override;
+    null_type_t null_;
+  };
+
+public:
+  identifier();
+
+  template<typename Type>
+  explicit identifier(const Type &id)
+  : id_(std::make_shared<pk<Type> >(id)) {
+  }
+
+  explicit identifier(const char *id)
+  : id_(std::make_shared<pk<std::string> >(id)) {
+  }
+
+  identifier(const identifier &x);
   identifier &operator=(const identifier &x);
-  identifier(identifier &&x) noexcept = default;
+  identifier(identifier &&x) noexcept;
-  identifier &operator=(identifier &&x) noexcept = default;
+  identifier &operator=(identifier &&x) noexcept;
 
-  explicit identifier(std::nullptr_t);
+  template<typename Type>
-  explicit identifier(const char *value);
+  identifier &operator=(const Type &value) {
-
+    id_ = std::make_shared<pk<Type> >(value);
-  identifier& operator=(std::nullptr_t);
-
-  template<typename Type, std::enable_if_t<std::is_integral_v<std::decay_t<Type>> && !std::is_same_v<std::decay_t<Type>, bool>, int> = 0>
-  identifier& operator=(Type value) {
-    assign_integral(value);
     return *this;
   }
 
-  identifier& operator=(const std::string &value);
+  identifier &operator=(const char *value) {
-  identifier& operator=(const char *value);
+    id_ = std::make_shared<pk<std::string> >(value);
-  template<typename Type, std::enable_if_t<is_identifier_supported_v<Type>  && std::is_same_v<std::decay_t<Type>, bool>, int> = 0>
-  identifier& operator=(Type &&value) {
-    value_ = std::forward<Type>(value);
     return *this;
   }
 
   ~identifier() = default;
 
-  result<void, error> assign(const value &val);
-
-  static result<identifier, error> from_value(const value &val);
-  [[nodiscard]] database_type to_database_type() const;
-
   bool operator==(const identifier &x) const;
   bool operator!=(const identifier &x) const;
   bool operator<(const identifier &x) const;
@@ -142,8 +180,17 @@ public:
   [[nodiscard]] const std::type_index &type_index() const;
   [[nodiscard]] basic_type type() const;
 
+  [[nodiscard]] identifier share() const;
+  [[nodiscard]] size_t use_count() const;
+
   [[nodiscard]] bool is_integer() const;
+  [[nodiscard]] bool is_floating_point() const;
+  [[nodiscard]] bool is_bool() const;
   [[nodiscard]] bool is_varchar() const;
+  [[nodiscard]] bool is_date() const;
+  [[nodiscard]] bool is_time() const;
+  [[nodiscard]] bool is_timestamp() const;
+  [[nodiscard]] bool is_blob() const;
   [[nodiscard]] bool is_null() const;
 
   [[nodiscard]] bool is_valid() const;
@@ -153,97 +200,15 @@ public:
 
   [[nodiscard]] size_t hash() const;
 
-  template <typename Type, std::enable_if_t<is_identifier_supported_v<Type>, int> = 0>
-  result<Type, error> as() const;
-
-  template <typename Type, std::enable_if_t<std::is_integral_v<Type> && !std::is_same_v<Type, bool>, int> = 0>
-  result<Type, error> convert() const;
-
   friend std::ostream &operator<<(std::ostream &out, const identifier &id);
 
 private:
-  template<typename Type>
+  explicit identifier(const std::shared_ptr<base> &id);
-  void assign_integral(Type value) {
-    if constexpr (std::is_signed_v<Type>) {
-      if (sizeof(Type) <= sizeof(int8_t)) {
-        value_ = static_cast<int8_t>(value);
-      } else if (sizeof(Type) <= sizeof(int16_t)) {
-        value_ = static_cast<int16_t>(value);
-      } else if (sizeof(Type) <= sizeof(int32_t)) {
-        value_ = static_cast<int32_t>(value);
-      } else {
-        value_ = static_cast<int64_t>(value);
-      }
-    } else {
-      if (sizeof(Type) <= sizeof(uint8_t)) {
-        value_ = static_cast<uint8_t>(value);
-      } else if (sizeof(Type) <= sizeof(uint16_t)) {
-        value_ = static_cast<uint16_t>(value);
-      } else if (sizeof(Type) <= sizeof(uint32_t)) {
-        value_ = static_cast<uint32_t>(value);
-      } else {
-        value_ = static_cast<uint64_t>(value);
-      }
-    }
-  }
-
-  static size_t type_rank(const value_type &value);
-  static std::type_index type_index_from_value(const value_type &value);
-  static basic_type type_from_value(const value_type &value);
 
 private:
-  value_type value_{std::monostate{}};
+  std::shared_ptr<base> id_;
 };
 
-template <typename Target, typename Source>
-bool in_range(Source value) {
-  if constexpr (std::is_signed_v<Source> == std::is_signed_v<Target>) {
-    return value >= static_cast<Target>(std::numeric_limits<Source>::min()) &&
-           value <= static_cast<Target>(std::numeric_limits<Source>::max());
-  } else if constexpr (std::is_signed_v<Source> && !std::is_signed_v<Target>) {
-    if (value < 0) {
-      return false;
-    }
-    using UnsignedSource = std::make_unsigned_t<Source>;
-    return static_cast<UnsignedSource>(value) <= std::numeric_limits<Target>::max();
-  } else {
-    return value <= static_cast<std::make_unsigned_t<Target>>(std::numeric_limits<Target>::max());
-  }
-}
-
-template <typename Type, std::enable_if_t<is_identifier_supported_v<Type>, int>>
-result<Type, error> identifier::as() const {
-  return std::visit([](const auto &v) -> result<Type, error> {
-    using StoredType = std::decay_t<decltype(v)>;
-
-    if constexpr (std::is_same_v<StoredType, std::monostate>) {
-      return failure(error{});
-    } else if constexpr (std::is_same_v<StoredType, Type>) {
-      return ok<Type>(v);
-    } else {
-      return failure(error{});
-    }
-  }, value_);
-}
-
-template <typename Type, std::enable_if_t<std::is_integral_v<Type> && !std::is_same_v<Type, bool>, int>>
-result<Type, error> identifier::convert() const {
-  return std::visit([](const auto &v) -> result<Type, error> {
-    using Stored = std::decay_t<decltype(v)>;
-
-    if constexpr (std::is_same_v<Stored, std::monostate>) {
-      return failure(error{});
-    } else if constexpr (std::is_integral_v<Stored>) {
-      if (!in_range<Type>(v)) {
-        return failure(error{});
-      }
-      return ok<Type>(static_cast<Type>(v));
-    } else {
-      return failure(error{});
-    }
-  }, value_);
-}
-
 static identifier null_identifier{};
 
 /// @cond MATADOR_DEV
@@ -254,11 +219,13 @@ struct id_pk_hash {
 /// @endcond
 }
 
+namespace std {
 template<>
-struct std::hash<matador::utils::identifier> {
+struct hash<matador::utils::identifier> {
   size_t operator()(const matador::utils::identifier &id) const noexcept {
     return id.hash();
   }
-}; // namespace std
+};
+} // namespace std
 
 #endif //MATADOR_IDENTIFIER_HPP

include/matador/utils/identifier_accessor.hpp

@@ -1,30 +0,0 @@
-#ifndef MATADOR_IDENTIFIER_ACCESSOR_HPP
-#define MATADOR_IDENTIFIER_ACCESSOR_HPP
-
-#include "matador/utils/identifier.hpp"
-#include "matador/utils/result.hpp"
-
-namespace matador::utils {
-class identifier_setter : public identifier_serializer {
-public:
-  explicit identifier_setter(identifier &id);
-
-  template <typename ValueType>
-  void set(const ValueType &val) {
-    id_.serialize(*this, val);
-  }
-  void serialize(int16_t &, const field_attributes &) override;
-  void serialize(int32_t &, const field_attributes &) override;
-  void serialize(int64_t &, const field_attributes &) override;
-  void serialize(uint8_t &, const field_attributes &) override;
-  void serialize(uint16_t &, const field_attributes &) override;
-  void serialize(uint32_t &, const field_attributes &) override;
-  void serialize(uint64_t &, const field_attributes &) override;
-  void serialize(std::string &, const field_attributes &) override;
-  void serialize(null_type_t &, const field_attributes &) override;
-
-private:
-  identifier &id_;
-};
-}
-#endif //MATADOR_IDENTIFIER_ACCESSOR_HPP

include/matador/utils/primary_key_accessor.hpp

@@ -1,125 +1,104 @@
 #ifndef MATADOR_PRIMARY_KEY_ACCESSOR_HPP
 #define MATADOR_PRIMARY_KEY_ACCESSOR_HPP
 
-#include "matador/utils/access.hpp"
 #include "matador/utils/field_attributes.hpp"
-#include "matador/utils/identifier.hpp"
 #include "matador/utils/primary_key_attribute.hpp"
 
 #include <cstdint>
 #include <string>
-#include <utility>
 
 namespace matador::utils {
 class foreign_attributes;
 namespace detail {
+template < typename PrimaryKeyType >
 class primary_key_setter {
 public:
-  template <typename ObjectType>
+  explicit primary_key_setter(const std::string &name, const PrimaryKeyType& value)
-  void set(ObjectType &obj, const identifier& pk) {
+  : name_(name)
-    pk_ = pk;
+  , value_(value){}
-    access::process(*this, obj);
-  }
 
-  template<typename PrimaryKeyType>
+  void on_primary_key(const char *id, PrimaryKeyType &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
-  void on_primary_key(const char * /*id*/, PrimaryKeyType &pk, const primary_key_attribute & = DefaultPkAttributes) {
+    if (id != nullptr && name_ == id) {
-    const auto value = pk_.as<PrimaryKeyType>();
+      pk = static_cast<PrimaryKeyType>(value_);
-    if (!value) {
-      // Todo: throw error
     }
-
-    pk = value.value();
   }
+  template<typename ValueType>
+  static void on_primary_key(const char * /*id*/, ValueType & /*pk*/, const utils::primary_key_attribute & = utils::default_pk_attributes) {}
   static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
   template<typename T>
-  static void on_attribute(const char * /*id*/, T &, const field_attributes & = NullAttributes) {}
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
   template<class P>
-  static void on_belongs_to(const char * /*id*/, P &, const foreign_attributes & ) {}
+  static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
   template<class P>
-  static void on_has_one(const char * /*id*/, P &, const foreign_attributes & ) {}
+  static void on_has_one(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const foreign_attributes & ) {}
+  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const foreign_attributes & ) {}
+  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many_to_many(const char * /*id*/, C &, const foreign_attributes & ) {}
+  static void on_has_many_to_many(const char * /*id*/, C &, const utils::foreign_attributes & ) {}
 
 private:
-  identifier pk_{};
+  const std::string &name_;
+  PrimaryKeyType value_{};
 };
 
 struct pk_unset_checker {
+  const std::string &name;
   bool unset{true};
 
-  template<class PrimaryKeyType>
+  template<class V>
-  void on_primary_key(const char * /*id*/, PrimaryKeyType &pk, const primary_key_attribute & = DefaultPkAttributes) {
+  void on_primary_key(const char *id, V &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
-    unset = !identifier_type_traits<PrimaryKeyType>::is_valid(pk);
+    if (id != nullptr && name == id) {
+      // Your convention: 0 means unset for integer PKs
+      unset = (static_cast<std::uint64_t>(pk) == 0ULL);
+    }
   }
   static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
   template<typename T>
-  static void on_attribute(const char * /*id*/, T &, const field_attributes & = NullAttributes) {}
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
   template<class P>
-  static void on_belongs_to(const char * /*id*/, P &, const foreign_attributes & ) {}
+  static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
   template<class P>
-  static void on_has_one(const char * /*id*/, P &, const foreign_attributes & ) {}
+  static void on_has_one(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const foreign_attributes & ) {}
+  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const foreign_attributes & ) {}
+  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many_to_many(const char * /*id*/, C &, const foreign_attributes & ) {}
+  static void on_has_many_to_many(const char * /*id*/, C &, const utils::foreign_attributes & ) {}
 };
 
-struct primary_key_getter {
+struct pk_value_extractor {
   std::uint64_t value{0};
 
-  template<class PrimaryKeyType>
+  template<class V>
-  void on_primary_key(const char * /*id*/, PrimaryKeyType &pk, const primary_key_attribute & = DefaultPkAttributes) {
+  void on_primary_key(const char * /*id*/, V &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
-    pk_ = pk;
+    value = static_cast<std::uint64_t>(pk);
   }
   static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
   template<typename T>
-  static void on_attribute(const char * /*id*/, T &, const field_attributes & = NullAttributes) {}
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
   template<class P>
-  static void on_belongs_to(const char * /*id*/, P &, const foreign_attributes & ) {}
+  static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
   template<class P>
-  static void on_has_one(const char * /*id*/, P &, const foreign_attributes & ) {}
+  static void on_has_one(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const foreign_attributes & ) {}
+  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const foreign_attributes & ) {}
+  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const utils::foreign_attributes & ) {}
   template<class C>
-  static void on_has_many_to_many(const char * /*id*/, C &, const foreign_attributes & ) {}
+  static void on_has_many_to_many(const char * /*id*/, C &, const utils::foreign_attributes & ) {}
-
-  identifier pk_;
 };
 
 }
 
+template<typename PrimaryKeyType>
 class primary_key_accessor {
 public:
-  template<class Type>
-  identifier get(const Type &obj) {
-    access::process(pk_getter_, obj);
-    return pk_getter_.pk_;
-  }
-
-  template<class Type>
-  void set(Type &obj, const identifier &pk) {
-    pk_setter_.set(obj, pk);
-  }
-
-  template<class Type>
-  bool is_set(const Type &obj) {
-    access::process(pk_unset_checker_, obj);
-    return !pk_unset_checker_.unset;
-  }
-
-private:
-  detail::primary_key_setter pk_setter_;
-  detail::pk_unset_checker pk_unset_checker_;
-  detail::primary_key_getter pk_getter_;
 
+  PrimaryKeyType get() const;
+  PrimaryKeyType
 };
 }
 

include/matador/utils/primary_key_attribute.hpp

@@ -47,7 +47,7 @@ private:
   generator_type generator_ = generator_type::Manual;
 };
 
-const primary_key_attribute DefaultPkAttributes {};
+const primary_key_attribute default_pk_attributes {};
 
 }
 #endif //PRIMARY_KEY_ATTRIBUTE_HPP

include/matador/utils/uuid.hpp

@@ -6,6 +6,7 @@
 #include <cstdint>
 
 namespace matador::utils {
+
 class uuid {
 public:
     using uuid_array = std::array<uint32_t, 4>;
@@ -38,7 +39,13 @@ private:
 // Hash specialization to allow use in unordered containers
 template <>
 struct std::hash<matador::utils::uuid> {
-  std::size_t operator()(const matador::utils::uuid &u) const noexcept;
+    std::size_t operator()(const matador::utils::uuid& u) const noexcept {
+        std::size_t h = 0;
+        for (const uint32_t val : u.data()) {
+            h ^= std::hash<uint32_t>{}(val) + 0x9e3779b9 + (h << 6) + (h >> 2);
+        }
+        return h;
+    }
 };
 
 #endif //MATADOR_UUID_HPP

source/core/CMakeLists.txt

@@ -22,14 +22,12 @@ add_library(matador-core STATIC
   ../../include/matador/object/collection_proxy.hpp
   ../../include/matador/object/collection_resolver.hpp
   ../../include/matador/object/collection_resolver_factory.hpp
-  ../../include/matador/object/collection_utils.hpp
   ../../include/matador/object/error_code.hpp
   ../../include/matador/object/foreign_node_completer.hpp
   ../../include/matador/object/internal/observer_list_copy_creator.hpp
   ../../include/matador/object/internal/observer_list_creator.hpp
   ../../include/matador/object/many_to_many_relation.hpp
   ../../include/matador/object/object.hpp
-  ../../include/matador/object/object_cache.hpp
   ../../include/matador/object/object_generator.hpp
   ../../include/matador/object/object_info.hpp
   ../../include/matador/object/object_proxy.hpp
@@ -37,7 +35,6 @@ add_library(matador-core STATIC
   ../../include/matador/object/object_resolver.hpp
   ../../include/matador/object/object_resolver_factory.hpp
   ../../include/matador/object/observer.hpp
-  ../../include/matador/object/pk_field_locator.hpp
   ../../include/matador/object/primary_key_resolver.hpp
   ../../include/matador/object/relation_completer.hpp
   ../../include/matador/object/relation_endpoint.hpp
@@ -66,7 +63,6 @@ add_library(matador-core STATIC
   ../../include/matador/utils/file.hpp
   ../../include/matador/utils/foreign_attributes.hpp
   ../../include/matador/utils/identifier.hpp
-  ../../include/matador/utils/identifier_accessor.hpp
   ../../include/matador/utils/identifier_to_value_converter.hpp
   ../../include/matador/utils/leader_follower_thread_pool.hpp
   ../../include/matador/utils/library.hpp
@@ -74,7 +70,6 @@ add_library(matador-core STATIC
   ../../include/matador/utils/message_bus.hpp
   ../../include/matador/utils/os.hpp
   ../../include/matador/utils/placeholder.hpp
-  ../../include/matador/utils/primary_key_accessor.hpp
   ../../include/matador/utils/primary_key_attribute.hpp
   ../../include/matador/utils/primary_key_generator_type.hpp
   ../../include/matador/utils/result.hpp
@@ -96,7 +91,6 @@ add_library(matador-core STATIC
   object/attribute.cpp
   object/basic_object_info.cpp
   object/basic_repository.cpp
-  object/collection_utils.cpp
   object/error_code.cpp
   object/foreign_node_completer.cpp
   object/object.cpp
@@ -114,7 +108,6 @@ add_library(matador-core STATIC
   utils/file.cpp
   utils/foreign_attributes.cpp
   utils/identifier.cpp
-  utils/identifier_accessor.cpp
   utils/identifier_to_value_converter.cpp
   utils/leader_follower_thread_pool.cpp
   utils/library.cpp
@@ -127,6 +120,11 @@ add_library(matador-core STATIC
   utils/uuid.cpp
   utils/value.cpp
   utils/version.cpp
+  ../../include/matador/object/collection_utils.hpp
+  object/collection_utils.cpp
+  ../../include/matador/object/pk_field_locator.hpp
+  ../../include/matador/object/object_cache.hpp
+  ../../include/matador/utils/primary_key_accessor.hpp
 )
 
 target_link_libraries(matador-core ${CMAKE_DL_LIBS})

source/core/object/object_generator.cpp

@@ -21,7 +21,7 @@ std::shared_ptr<object> object_generator::acquire_object(basic_repository &repo,
 }
 
 void object_generator::on_revision(const char* id, uint64_t& rev) {
-    access::attribute(*this, id, rev);
+  on_attribute(id, rev);
 }
 
 void object_generator::create_pk_constraint(const std::string& name) const {

source/core/utils/errors.cpp

@@ -10,8 +10,6 @@ std::string utils_category_impl::message(const int ev) const {
   switch (static_cast<utils_error>(ev)) {
     case (utils_error::InvalidVersionString):
       return "Invalid version string";
-    case utils_error::IdentifierTypeMismatch:
-      return "Identifier type mismatch";
     default:
       return "Unknown error";
   }

source/core/utils/identifier.cpp

@@ -1,234 +1,97 @@
 #include "matador/utils/identifier.hpp"
 
-#include "matador/utils/value.hpp"
+#include <cstring>
-#include "matador/utils/errors.hpp"
+#include <stdexcept>
-
 #include <ostream>
-#include <utility>
 
 namespace matador::utils {
+size_t detail::hash(const char *value) {
+  return std::hash<std::string_view>()(std::string_view(value, std::strlen(value)));
+}
 
-namespace {
+bool identifier_type_traits<const char *>::is_valid(const char *value) {
-inline const std::type_index& null_type_index() {
+  return value != nullptr && strlen(value) > 0;
-  static const std::type_index value{typeid(null_type_t)};
+}
+
+std::string identifier_type_traits<const char *>::to_string(const char *value) {
   return value;
 }
 
-inline const std::type_index& i8_type_index() {
+identifier::base::base(const std::type_index &ti, const basic_type type)
-  static const std::type_index value{typeid(int8_t)};
+: type_index_(ti)
-  return value;
+  , type_(type) {
 }
 
-inline const std::type_index& i16_type_index() {
+identifier::null_pk::null_pk()
-  static const std::type_index value{typeid(int16_t)};
+: base(std::type_index(typeid(null_type_t)), basic_type::Null) {
-  return value;
 }
 
-inline const std::type_index& i32_type_index() {
+identifier::base *identifier::null_pk::copy() const {
-  static const std::type_index value{typeid(int32_t)};
+  return new null_pk;
-  return value;
 }
 
-inline const std::type_index& i64_type_index() {
+bool identifier::null_pk::equal_to(const base &x) const {
-  static const std::type_index value{typeid(int64_t)};
+  return type_index_ == x.type_index_;
-  return value;
 }
 
-inline const std::type_index& u8_type_index() {
+bool identifier::null_pk::less(const base &x) const {
-  static const std::type_index value{typeid(uint8_t)};
+  return type_index_ == x.type_index_;
-  return value;
 }
 
-inline const std::type_index& u16_type_index() {
+bool identifier::null_pk::is_valid() const {
-  static const std::type_index value{typeid(uint16_t)};
+  return identifier_type_traits<null_type_t>::is_valid();
-  return value;
 }
 
-inline const std::type_index& u32_type_index() {
+std::string identifier::null_pk::str() const {
-  static const std::type_index value{typeid(uint32_t)};
+  return identifier_type_traits<null_type_t>::to_string();
-  return value;
 }
 
-inline const std::type_index& u64_type_index() {
+void identifier::null_pk::serialize(identifier_serializer &s) {
-  static const std::type_index value{typeid(uint64_t)};
+  s.serialize(null_, {});
-  return value;
 }
 
-inline const std::type_index& string_type_index() {
+size_t identifier::null_pk::hash() const {
-  static const std::type_index value{typeid(std::string)};
+  return std::hash<nullptr_t>()(nullptr);
-  return value;
-}
-} // namespace
-
-size_t detail::hash(const std::string &value) {
-  return std::hash<std::string_view>()(std::string_view(value));
 }
 
 identifier::identifier()
-: value_(std::monostate{}) {
+: id_(std::make_shared<null_pk>()) {
 }
 
-size_t identifier::type_rank(const value_type &value) {
+identifier::identifier(const identifier &x)
-  return value.index();
+: id_(x.id_->copy()) {
 }
 
-std::type_index identifier::type_index_from_value(const value_type &value) {
+identifier &identifier::operator=(const identifier &x) {
-  return std::visit([](const auto &v) -> std::type_index {
+  if (this == &x) {
-    using T = std::decay_t<decltype(v)>;
+    return *this;
-    if constexpr (std::is_same_v<T, std::monostate>) {
-      return null_type_index();
-    } else {
-      return std::type_index(typeid(T));
   }
-  }, value);
+  id_.reset(x.id_->copy());
-}
-
-const std::type_index &identifier::type_index() const {
-  switch (value_.index()) {
-    case 0: return null_type_index();
-    case 1: return i8_type_index();
-    case 2: return i16_type_index();
-    case 3: return i32_type_index();
-    case 4: return i64_type_index();
-    case 5: return u8_type_index();
-    case 6: return u16_type_index();
-    case 7: return u32_type_index();
-    case 8: return u64_type_index();
-    case 9: return string_type_index();
-    default: return null_type_index();
-  }
-}
-
-basic_type identifier::type_from_value(const value_type &value) {
-  return std::visit([](const auto &v) -> basic_type {
-    using T = std::decay_t<decltype(v)>;
-    if constexpr (std::is_same_v<T, std::monostate>) {
-      return basic_type::Null;
-    } else {
-      return data_type_traits<T>::type(1);
-    }
-  }, value);
-}
-
-identifier::identifier(std::nullptr_t)
-: value_(std::monostate{}) {
-}
-
-identifier::identifier(const char *value)
-: value_(value ? std::string(value) : std::string{}) {
-}
-
-identifier & identifier::operator=(const char *value) {
-  value_ = value ? std::string(value) : std::string{};
   return *this;
 }
 
-result<identifier, error> identifier::from_value(const value &val) {
+identifier::identifier(identifier &&x) noexcept
-  identifier id;
+: id_(std::move(x.id_)) {
-  if (const auto result = id.assign(val); result.is_error()) {
+  x.clear();
-    return failure(result.err());
 }
 
-  return ok(id);
+identifier &identifier::operator=(identifier &&x) noexcept {
-}
+  id_ = std::move(x.id_);
+  x.clear();
 
-database_type identifier::to_database_type() const {
+  return *this;
-  return std::visit([](const auto &v) -> database_type {
-          using T = std::decay_t<decltype(v)>;
-
-          if constexpr (std::is_same_v<T, std::monostate>) {
-            return nullptr;
-          } else if constexpr (std::is_same_v<T, std::string>) {
-            return v;
-          } else {
-            return static_cast<T>(v);
-          }
-        }, value_);
-}
-
-result<void, error> identifier::assign(const value &val) {
-  switch (val.type()) {
-    case basic_type::Null:
-      value_ = std::monostate{};
-      return ok<void>{};
-
-    case basic_type::Int8:
-      if (auto v = val.as<int8_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-    case basic_type::Int16:
-      if (auto v = val.as<int16_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-    case basic_type::Int32:
-      if (auto v = val.as<int32_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-    case basic_type::Int64:
-      if (auto v = val.as<int64_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-
-    case basic_type::UInt8:
-      if (auto v = val.as<uint8_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-    case basic_type::UInt16:
-      if (auto v = val.as<uint16_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-    case basic_type::UInt32:
-      if (auto v = val.as<uint32_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-    case basic_type::UInt64:
-      if (auto v = val.as<uint64_t>()) { value_ = *v; return ok<void>{}; }
-      break;
-
-    case basic_type::Text:
-    case basic_type::Varchar:
-      if (auto v = val.as<std::string>()) { value_ = *v; return ok<void>{}; }
-      break;
-
-    default:
-      break;
-  }
-
-  return failure(error{utils_error::IdentifierTypeMismatch});
 }
 
 bool identifier::operator==(const identifier &x) const {
-  return value_ == x.value_;
+  return id_->equal_to(*x.id_);
 }
 
 bool identifier::operator!=(const identifier &x) const {
   return !operator==(x);
 }
 
-identifier &identifier::operator=(std::nullptr_t) {
-  value_ = std::monostate{};
-  return *this;
-}
-
-identifier &identifier::operator=(const std::string &value) {
-  value_ = value;
-  return *this;
-}
-
-identifier &identifier::operator=(const identifier &other) {
-  if (this != &other) {
-    value_ = other.value_;
-  }
-  return *this;
-}
-
 bool identifier::operator<(const identifier &x) const {
-  if (value_.index() != x.value_.index()) {
+  return id_->less(*x.id_);
-    return value_.index() < x.value_.index();
-  }
-
-  return std::visit([](const auto &lhs, const auto &rhs) -> bool {
-    using L = std::decay_t<decltype(lhs)>;
-    using R = std::decay_t<decltype(rhs)>;
-    if constexpr (std::is_same_v<L, R>) {
-      return lhs < rhs;
-    } else {
-      return false;
-    }
-  }, value_, x.value_);
 }
 
 bool identifier::operator<=(const identifier &x) const {
@@ -244,78 +107,79 @@ bool identifier::operator>=(const identifier &x) const {
 }
 
 std::string identifier::str() const {
-  return std::visit([](const auto &v) -> std::string {
+  return id_->str();
-    using T = std::decay_t<decltype(v)>;
-    if constexpr (std::is_same_v<T, std::monostate>) {
-      return identifier_type_traits<null_type_t>::to_string();
-    } else if constexpr (std::is_same_v<T, std::string>) {
-      return identifier_type_traits<std::string>::to_string(v);
-    } else {
-      return identifier_type_traits<T>::to_string(v);
 }
-  }, value_);
+
+const std::type_index &identifier::type_index() const {
+  return id_->type_index_;
 }
 
 basic_type identifier::type() const {
-  return type_from_value(value_);
+  return id_->type_;
+}
+
+identifier identifier::share() const {
+  return identifier(id_);
+}
+
+size_t identifier::use_count() const {
+  return id_.use_count();
 }
 
 bool identifier::is_integer() const {
-  return std::holds_alternative<int8_t>(value_)
+  return id_->type_ >= basic_type::Int8 && id_->type_ <= basic_type::UInt64;
-      || std::holds_alternative<int16_t>(value_)
+}
-      || std::holds_alternative<int32_t>(value_)
+
-      || std::holds_alternative<int64_t>(value_)
+bool identifier::is_floating_point() const {
-      || std::holds_alternative<uint8_t>(value_)
+  return id_->type_ == basic_type::Float || id_->type_ == basic_type::Double;
-      || std::holds_alternative<uint16_t>(value_)
+}
-      || std::holds_alternative<uint32_t>(value_)
+
-      || std::holds_alternative<uint64_t>(value_);
+bool identifier::is_bool() const {
+  return id_->type_ == basic_type::Boolean;
 }
 
 bool identifier::is_varchar() const {
-  return std::holds_alternative<std::string>(value_);
+  return id_->type_ == basic_type::Varchar;
+}
+
+bool identifier::is_date() const {
+  return id_->type_ == basic_type::Date;
+}
+
+bool identifier::is_time() const {
+  return id_->type_ == basic_type::Time;
+}
+
+bool identifier::is_timestamp() const {
+  return id_->type_ == basic_type::DateTime;
+}
+
+bool identifier::is_blob() const {
+  return id_->type_ == basic_type::Blob;
 }
 
 bool identifier::is_null() const {
-  return std::holds_alternative<std::monostate>(value_);
+  return type_index() == null_identifier.type_index();
 }
 
 bool identifier::is_valid() const {
-  return std::visit([](const auto &v) -> bool {
+  return id_->is_valid();
-    using T = std::decay_t<decltype(v)>;
-    if constexpr (std::is_same_v<T, std::monostate>) {
-      return identifier_type_traits<null_type_t>::is_valid();
-    } else {
-      return identifier_type_traits<T>::is_valid(v);
-    }
-  }, value_);
 }
 
 void identifier::clear() {
-  value_ = std::monostate{};
+  id_ = std::make_unique<null_pk>();
 }
 
 void identifier::serialize(identifier_serializer &s) const {
-  std::visit([&s](const auto &v) {
+  id_->serialize(s);
-    using T = std::decay_t<decltype(v)>;
-    if constexpr (std::is_same_v<T, std::monostate>) {
-      null_type_t n{};
-      s.serialize(n, {});
-    } else {
-      auto tmp = v;
-      s.serialize(tmp, {});
-    }
-  }, value_);
 }
 
 size_t identifier::hash() const {
-  return std::visit([](const auto &v) -> size_t {
+  return id_->hash();
-    using T = std::decay_t<decltype(v)>;
-    if constexpr (std::is_same_v<T, std::monostate>) {
-      return std::hash<int>{}(0);
-    } else {
-      return detail::hash(v);
 }
-  }, value_);
+
+identifier::identifier(const std::shared_ptr<base> &id)
+: id_(id) {
 }
 
 std::ostream &operator<<(std::ostream &out, const identifier &id) {
@@ -326,5 +190,4 @@ std::ostream &operator<<(std::ostream &out, const identifier &id) {
 size_t id_pk_hash::operator()(const identifier &id) const {
   return id.hash();
 }
-
+}
-} // namespace matador::utils

source/core/utils/identifier_accessor.cpp

@@ -1,38 +0,0 @@
-#include "matador/utils/identifier_accessor.hpp"
-#include "matador/utils/default_type_traits.hpp"
-
-namespace matador::utils {
-identifier_setter::identifier_setter(identifier &id)
-: id_(id) {
-}
-
-void identifier_setter::serialize(int16_t &val, const field_attributes &) {
-  if (id_.type() == data_type_traits<int16_t>::type()) {
-    id_ = val;
-  }
-}
-
-void identifier_setter::serialize(int32_t &, const field_attributes &) {
-}
-
-void identifier_setter::serialize(int64_t &, const field_attributes &) {
-}
-
-void identifier_setter::serialize(uint8_t &, const field_attributes &) {
-}
-
-void identifier_setter::serialize(uint16_t &, const field_attributes &) {
-}
-
-void identifier_setter::serialize(uint32_t &, const field_attributes &) {
-}
-
-void identifier_setter::serialize(uint64_t &, const field_attributes &) {
-}
-
-void identifier_setter::serialize(std::string &, const field_attributes &) {
-}
-
-void identifier_setter::serialize(null_type_t &, const field_attributes &) {
-}
-}

source/core/utils/uuid.cpp

@@ -3,6 +3,7 @@
 #include <random>
 
 namespace matador::utils {
+
 uuid uuid::generate() {
     std::random_device rd;
     std::mt19937_64 gen(rd());
@@ -72,11 +73,3 @@ bool operator<(const uuid &lhs, const uuid &rhs) {
     return lhs._data < rhs._data;
 }
 }
-
-std::size_t std::hash<matador::utils::uuid>::operator()(const matador::utils::uuid &u) const noexcept {
-  std::size_t h = 0;
-  for (const uint32_t val: u.data()) {
-    h ^= std::hash<uint32_t>{}(val) + 0x9e3779b9 + (h << 6) + (h >> 2);
-  }
-  return h;
-}

source/orm/sql/field.cpp

@@ -62,10 +62,6 @@ int field::index() const {
   return index_;
 }
 
-utils::value field::value() const {
-  return value_;
-}
-
 std::ostream &operator<<(std::ostream &out, const field &col) {
   out << col.str();
   return out;

test/backends/SessionInsertHasMany.cpp

@@ -10,7 +10,7 @@ using namespace matador::object;
 using namespace matador::test;
 
 TEST_CASE_METHOD(SessionFixture, "Test insert object with has many relation", "[session][insert][has_many]") {
-  const auto result = schema.attach<book>("books")
+  auto result = schema.attach<book>("books")
     .and_then( [this] { return schema.attach<author>("authors"); } )
     .and_then([this] { return schema.create(db); } );
   REQUIRE(result.is_ok());

test/core/CMakeLists.txt

@@ -5,7 +5,6 @@ list(APPEND CMAKE_MODULE_PATH ${catch2_SOURCE_DIR}/extras)
 add_executable(CoreTests
   ../backends/SchemaFixture.hpp
   logger/LoggerTest.cpp
-  object/ObjectCacheTest.cpp
   object/ObjectTest.cpp
   object/PrimaryKeyResolverTest.cpp
   object/RepositoryTest.cpp
@@ -15,13 +14,13 @@ add_executable(CoreTests
   utils/DependencyInjectionTest.cpp
   utils/FieldAttributeTest.cpp
   utils/IdentifierTest.cpp
-  utils/IsDatabasePrimitiveTest.cpp
   utils/MessageBusTest.cpp
-  utils/PrimaryKeyAccessorTest.cpp
   utils/ResultTest.cpp
   utils/StringTest.cpp
   utils/ThreadPoolTest.cpp
   utils/VersionTest.cpp
+  utils/IsDatabasePrimitiveTest.cpp
+  object/ObjectCacheTest.cpp
 )
 
 target_link_libraries(CoreTests matador-core Catch2::Catch2WithMain)

test/core/utils/IdentifierTest.cpp

@@ -2,7 +2,6 @@
 
 #include "matador/utils/identifier.hpp"
 #include "matador/utils/default_type_traits.hpp"
-#include "matador/utils/value.hpp"
 
 using namespace matador::utils;
 
@@ -11,7 +10,12 @@ TEST_CASE("Test create identifier", "[identifier][create]") {
 
   REQUIRE(id.is_null());
   REQUIRE(!id.is_integer());
+  REQUIRE(!id.is_floating_point());
+  REQUIRE(!id.is_bool());
   REQUIRE(!id.is_varchar());
+  REQUIRE(!id.is_date());
+  REQUIRE(!id.is_time());
+  REQUIRE(!id.is_blob());
   REQUIRE(!id.is_valid());
   REQUIRE(id.str() == "null");
 }
@@ -84,7 +88,7 @@ TEST_CASE("Test copy identifier" "[identifier][copy]") {
   identifier id3 = id1;
 
   REQUIRE(id1 == id3);
-  REQUIRE(!(id1 < id3));
+  REQUIRE(id1 < id3);
   REQUIRE(id3.is_null());
   REQUIRE(id1.hash() == id3.hash());
 
@@ -99,268 +103,16 @@ TEST_CASE("Test move identifier", "[identifier][move]") {
   REQUIRE(!id1.is_null());
 
   const auto id2 = std::move(id1);
-  REQUIRE(!id1.is_null());
+  REQUIRE(id1.is_null());
   REQUIRE(id2.is_integer());
 }
 
-TEST_CASE("identifier assignment from integer types", "[utils][identifier][assign]") {
+TEST_CASE("Test share identifier", "[identifier][share]") {
-  identifier id;
+  const identifier id1{6};
 
-  id = int8_t{-5};
+  REQUIRE(id1.use_count() == 1);
-  REQUIRE(id.type() == basic_type::Int8);
-  REQUIRE(id.str() == "-5");
-  REQUIRE(id.is_integer());
-  REQUIRE(id.is_valid());
 
-  id = int16_t{42};
+  auto id2 = id1.share();
-  REQUIRE(id.type() == basic_type::Int16);
+  REQUIRE(id1 == id2);
-  REQUIRE(id.str() == "42");
+  REQUIRE(id1.use_count() == 2);
-  REQUIRE(id.is_integer());
-  REQUIRE(id.is_valid());
-
-  id = uint32_t{123456u};
-  REQUIRE(id.type() == basic_type::UInt32);
-  REQUIRE(id.str() == "123456");
-  REQUIRE(id.is_integer());
-  REQUIRE(id.is_valid());
-}
-
-TEST_CASE("identifier assignment from string type", "[utils][identifier][assign]") {
-  identifier id;
-
-  id = std::string{"hello"};
-  REQUIRE(id.type() == basic_type::Varchar);
-  REQUIRE(id.str() == "hello");
-  REQUIRE(id.is_varchar());
-  REQUIRE(id.is_valid());
-
-  id = std::string{};
-  REQUIRE(id.type() == basic_type::Varchar);
-  REQUIRE(id.str().empty());
-  REQUIRE_FALSE(id.is_valid());
-}
-
-TEST_CASE("identifier assignment from const char*", "[utils][identifier][assign]") {
-  identifier id;
-
-  id = "world";
-  REQUIRE(id.type() == basic_type::Varchar);
-  REQUIRE(id.str() == "world");
-  REQUIRE(id.is_varchar());
-  REQUIRE(id.is_valid());
-
-  id = static_cast<const char*>(nullptr);
-  REQUIRE(id.type() == basic_type::Varchar);
-  REQUIRE(id.str().empty());
-  REQUIRE_FALSE(id.is_valid());
-}
-
-TEST_CASE("identifier assignment from nullptr", "[utils][identifier][assign]") {
-  identifier id{42};
-
-  REQUIRE(id.is_valid());
-  REQUIRE_FALSE(id.is_null());
-
-  id = nullptr;
-  REQUIRE(id.is_null());
-  REQUIRE(id.type() == basic_type::Null);
-  REQUIRE(id.str() == "null");
-  REQUIRE_FALSE(id.is_valid());
-}
-
-TEST_CASE("identifier reassignment between types", "[utils][identifier][assign]") {
-  identifier id{uint64_t{7}};
-
-  REQUIRE(id.is_integer());
-  REQUIRE(id.str() == "7");
-
-  id = std::string{"abc"};
-  REQUIRE(id.is_varchar());
-  REQUIRE(id.str() == "abc");
-  REQUIRE(id.is_valid());
-
-  id = int64_t{99};
-  REQUIRE(id.is_integer());
-  REQUIRE(id.str() == "99");
-  REQUIRE(id.is_valid());
-
-  id = nullptr;
-  REQUIRE(id.is_null());
-  REQUIRE(id.str() == "null");
-}
-
-TEST_CASE("identifier as() returns exact integer type", "[utils][identifier][as]") {
-  identifier id{int32_t{42}};
-
-  const auto as_i32 = id.as<int32_t>();
-  REQUIRE(as_i32.is_ok());
-  REQUIRE(*as_i32 == 42);
-
-  const auto as_i64 = id.as<int64_t>();
-  REQUIRE(as_i64.is_error());
-}
-
-TEST_CASE("identifier as() returns exact string type", "[utils][identifier][as]") {
-  identifier id{std::string{"hello"}};
-
-  const auto as_string = id.as<std::string>();
-  REQUIRE(as_string.is_ok());
-  REQUIRE(*as_string == "hello");
-
-  const auto as_i32 = id.as<int32_t>();
-  REQUIRE(as_i32.is_error());
-}
-
-TEST_CASE("identifier as() returns null type failure for null identifier", "[utils][identifier][as]") {
-  identifier id{nullptr};
-
-  const auto as_i32 = id.as<int32_t>();
-  REQUIRE(as_i32.is_error());
-
-  const auto as_string = id.as<std::string>();
-  REQUIRE(as_string.is_error());
-}
-
-TEST_CASE("identifier convert() converts between integer types", "[utils][identifier][convert]") {
-  identifier id{int32_t{123}};
-
-  const auto as_i64 = id.convert<int64_t>();
-  REQUIRE(as_i64.is_ok());
-  REQUIRE(*as_i64 == 123);
-
-  const auto as_u8 = id.convert<uint8_t>();
-  REQUIRE(as_u8.is_ok());
-  REQUIRE(*as_u8 == 123);
-}
-
-TEST_CASE("identifier convert() rejects out of range integer conversion", "[utils][identifier][convert]") {
-  identifier id{int32_t{300}};
-
-  const auto as_u8 = id.convert<uint8_t>();
-  REQUIRE(as_u8.is_error());
-}
-
-TEST_CASE("identifier convert() rejects negative to unsigned conversion", "[utils][identifier][convert]") {
-  identifier id{int32_t{-1}};
-
-  const auto as_u32 = id.convert<uint32_t>();
-  REQUIRE(as_u32.is_error());
-}
-
-TEST_CASE("identifier convert() rejects non-integer source types", "[utils][identifier][convert]") {
-  identifier id{std::string{"123"}};
-
-  const auto as_i32 = id.convert<int32_t>();
-  REQUIRE(as_i32.is_error());
-
-  identifier null_id{nullptr};
-  const auto null_to_i64 = null_id.convert<int64_t>();
-  REQUIRE(null_to_i64.is_error());
-}
-
-TEST_CASE("identifier convert() works with unsigned integer sources", "[utils][identifier][convert]") {
-  identifier id{uint16_t{500}};
-
-  const auto as_i32 = id.convert<int32_t>();
-  REQUIRE(as_i32.is_ok());
-  REQUIRE(*as_i32 == 500);
-
-  const auto as_u8 = id.convert<uint8_t>();
-  REQUIRE(as_u8.is_error());
-}
-
-TEST_CASE("identifier as() and convert() behave consistently for same integer type", "[utils][identifier][as][convert]") {
-  identifier id{uint64_t{77}};
-
-  const auto as_u64 = id.as<uint64_t>();
-  REQUIRE(as_u64.is_ok());
-  REQUIRE(*as_u64 == 77);
-
-  const auto conv_u64 = id.convert<uint64_t>();
-  REQUIRE(conv_u64.is_ok());
-  REQUIRE(*conv_u64 == 77);
-}
-
-TEST_CASE("identifier assign from value", "[utils][identifier][assign]") {
-  identifier id;
-
-  value v1{int32_t{17}};
-  const auto r1 = id.assign(v1);
-  REQUIRE(r1.is_ok());
-  REQUIRE(id.is_integer());
-  REQUIRE(id.str() == "17");
-
-  value v2{std::string{"abc"}};
-  const auto r2 = id.assign(v2);
-  REQUIRE(r2.is_ok());
-  REQUIRE(id.is_varchar());
-  REQUIRE(id.str() == "abc");
-
-  value v3{basic_type::Double, 0};
-  const auto r3 = id.assign(v3);
-  REQUIRE(r3.is_error());
-}
-
-TEST_CASE("identifier assign from value with exact type mapping", "[utils][identifier][assign]") {
-  identifier id;
-
-  SECTION("integer types") {
-    value v{int16_t{12}};
-    const auto r = id.assign(v);
-    REQUIRE(r.is_ok());
-    REQUIRE(id.is_integer());
-    REQUIRE(id.str() == "12");
-  }
-
-  SECTION("string types") {
-    value v{std::string{"abc"}};
-    const auto r = id.assign(v);
-    REQUIRE(r.is_ok());
-    REQUIRE(id.is_varchar());
-    REQUIRE(id.str() == "abc");
-  }
-
-  SECTION("null") {
-    value v{basic_type::Null, 0};
-    const auto r = id.assign(v);
-    REQUIRE(r.is_ok());
-    REQUIRE(id.is_null());
-  }
-}
-
-TEST_CASE("identifier::to_database_type converts internal value to database_type", "[identifier]") {
-  SECTION("null identifier becomes nullptr") {
-    identifier id{nullptr};
-
-    const auto db_value = id.to_database_type();
-
-    REQUIRE(std::holds_alternative<std::nullptr_t>(db_value));
-  }
-
-  SECTION("signed integral identifier becomes same signed database type") {
-    identifier id{int32_t{42}};
-
-    const auto db_value = id.to_database_type();
-
-    REQUIRE(std::holds_alternative<int32_t>(db_value));
-    REQUIRE(std::get<int32_t>(db_value) == 42);
-  }
-
-  SECTION("unsigned integral identifier becomes same unsigned database type") {
-    identifier id{uint64_t{123456789ULL}};
-
-    const auto db_value = id.to_database_type();
-
-    REQUIRE(std::holds_alternative<uint64_t>(db_value));
-    REQUIRE(std::get<uint64_t>(db_value) == 123456789ULL);
-  }
-
-  SECTION("string identifier becomes std::string database type") {
-    identifier id{std::string{"customer_1"}};
-
-    const auto db_value = id.to_database_type();
-
-    REQUIRE(std::holds_alternative<std::string>(db_value));
-    REQUIRE(std::get<std::string>(db_value) == "customer_1");
-  }
 }

test/core/utils/PrimaryKeyAccessorTest.cpp

@@ -1,68 +0,0 @@
-#include <catch2/catch_test_macros.hpp>
-
-#include "matador/utils/identifier.hpp"
-#include "matador/utils/primary_key_accessor.hpp"
-
-#include "../test/models/person.hpp"
-
-TEST_CASE("primary_key_accessor detects unset primary key", "[utils][primary_key_accessor]") {
-  using namespace matador;
-
-  utils::primary_key_accessor accessor;
-  test::person p{};
-
-  REQUIRE_FALSE(accessor.is_set(p));
-}
-
-TEST_CASE("primary_key_accessor detects set primary key", "[utils][primary_key_accessor]") {
-  using namespace matador;
-
-  utils::primary_key_accessor accessor;
-  test::person p{};
-  p.id = 42;
-
-  REQUIRE(accessor.is_set(p));
-}
-
-TEST_CASE("primary_key_accessor gets integer primary key", "[utils][primary_key_accessor]") {
-  using namespace matador;
-
-  utils::primary_key_accessor accessor;
-  test::person p{};
-  p.id = 17;
-
-  const auto pk = accessor.get(p);
-
-  REQUIRE(pk.is_integer());
-  REQUIRE(pk.is_valid());
-  REQUIRE(pk.as<unsigned int>().is_ok());
-  REQUIRE(*pk.as<unsigned int>() == 17u);
-}
-
-TEST_CASE("primary_key_accessor sets integer primary key", "[utils][primary_key_accessor]") {
-  using namespace matador;
-
-  utils::primary_key_accessor accessor;
-  test::person p{};
-
-  accessor.set(p, utils::identifier{123u});
-
-  REQUIRE(p.id == 123u);
-  REQUIRE(accessor.is_set(p));
-}
-
-TEST_CASE("primary_key_accessor can round-trip primary key value", "[utils][primary_key_accessor]") {
-  using namespace matador;
-
-  utils::primary_key_accessor accessor;
-  test::person original{};
-  original.id = 88u;
-
-  const auto pk = accessor.get(original);
-
-  test::person copy{};
-  accessor.set(copy, pk);
-
-  REQUIRE(copy.id == 88u);
-  REQUIRE(accessor.is_set(copy));
-}

test/models/coordinate.hpp

@@ -14,7 +14,7 @@ struct coordinate {
 
 namespace matador::access {
 template<class Operator>
-void attribute(Operator &op, const char *id, test::coordinate &value, const utils::field_attributes &attr = utils::NullAttributes) {
+void attribute(Operator &op, const char *id, test::coordinate &value, const utils::field_attributes &attr = utils::null_attributes) {
   attribute(op, (std::string(id) + "_x").c_str(), value.x, attr);
   attribute(op, (std::string(id) + "_y").c_str(), value.y, attr);
   attribute(op, (std::string(id) + "_z").c_str(), value.z, attr);

test/orm/query/InsertQueryBuilderTest.cpp

@@ -12,8 +12,6 @@
 
 #include "../backend/test_backend_service.hpp"
 
-#include "../../models/author.hpp"
-#include "../../models/book.hpp"
 #include "../../models/airplane.hpp"
 #include "../../models/flight.hpp"
 
@@ -34,8 +32,8 @@ TEST_CASE("insert query builder test", "[query][insert_query_builder]") {
 
   insert_query_builder iqb(scm);
 
-  const auto a380 = make_object<airplane>(1, "Boeing", "A380"  );
+  const auto a380 = object_ptr(std::make_shared<airplane>(1, "Boeing", "A380"  ));
-  auto build_result = iqb.build(a380);
+  auto build_result = iqb.build<airplane>(a380);
   REQUIRE(build_result.is_ok());
 
   const auto& stmts = *build_result;
@@ -47,30 +45,3 @@ TEST_CASE("insert query builder test", "[query][insert_query_builder]") {
   const auto sql = std::get<executable_query>(step.query).str(db);
   REQUIRE(sql == R"(INSERT INTO "airplanes" ("id", "brand", "model") VALUES (1, 'Boeing', 'A380'))");
 }
-
-TEST_CASE("Test insert builder has many", "[query][insert_query_builder][has_many]") {
-  using namespace matador::test;
-  backend_provider::instance().register_backend("noop", std::make_unique<orm::test_backend_service>());
-  connection db("noop://noop.db");
-
-  schema scm;
-  const auto result = scm.attach<book>("books")
-    .and_then( [&scm] { return scm.attach<author>("authors"); } );
-  REQUIRE(result.is_ok());
-
-  auto s_king = make_object<author>(1, "Steven", "King", "21.9.1947", 1956, false);
-
-  s_king->books.push_back(make_object<book>(2, "Carrie", object_ptr<author>{}, 1974));
-  s_king->books.push_back(make_object<book>(3, "The Shining", object_ptr<author>{}, 1977));
-  s_king->books.push_back(make_object<book>(4, "It", object_ptr<author>{}, 1986));
-  s_king->books.push_back(make_object<book>(5, "Misery", object_ptr<author>{}, 1987));
-  s_king->books.push_back(make_object<book>(6, "The Dark Tower: The Gunslinger", object_ptr<author>{}, 1982));
-
-  insert_query_builder iqb(scm);
-
-  auto build_result = iqb.build(s_king);
-  REQUIRE(build_result.is_ok());
-
-  const auto& stmts = *build_result;
-  REQUIRE(stmts.size() == 1);
-}