diff --git a/include/matador/object/attribute_generator.hpp b/include/matador/object/attribute_generator.hpp
index 2392015..8459fc9 100644
--- a/include/matador/object/attribute_generator.hpp
+++ b/include/matador/object/attribute_generator.hpp
@@ -7,6 +7,7 @@
 #include "matador/utils/data_type_traits.hpp"
 #include "matador/utils/error.hpp"
 #include "matador/utils/field_attributes.hpp"
+#include "matador/utils/identifier.hpp"
 #include "matador/utils/primary_key_attribute.hpp"
 #include "matador/utils/result.hpp"
 
@@ -91,9 +92,7 @@ public:
     on_foreign_key(id, x);
   }
   template<class Pointer>
-  void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {
-    // on_foreign_key(id, x);
-  }
+  static void on_has_one(const char * /*id*/, Pointer &/*x*/, const utils::foreign_attributes &/*attr*/) {}
 
   template <class Pointer>
   void on_foreign_key(const char *id, Pointer &x) {
@@ -123,6 +122,15 @@ private:
   [[nodiscard]] utils::result<std::shared_ptr<attribute>, utils::error> determine_foreign_ref(const std::type_index &ti) const;
   void insert_missing_reference_column(const std::type_index &ti, const std::shared_ptr<attribute>& ref_column) const;
 
+  template<typename ValueType>
+  attribute &emplace_attribute(const char *id, const utils::field_attributes& attr, null_option_type null_option) {
+    auto &ref = columns_.emplace_back(id, utils::data_type_traits<ValueType>::type(attr.size()), attr, null_option);
+    ref.owner_ = &obj_;
+    return ref;
+  }
+
+  void prepare_primary_key(attribute &ref, utils::identifier &&pk) const;
+
 private:
   size_t index_ = 0;
   std::vector<attribute> &columns_;
@@ -134,19 +142,18 @@ private:
 
 template<typename ValueType>
 void attribute_generator::on_primary_key(const char *id, ValueType &x, const utils::primary_key_attribute& attr) {
-  on_attribute(id, x, { attr.size(), utils::constraints::PrimaryKey });
+  auto &ref = emplace_attribute<ValueType>(id, { attr.size(), utils::constraints::PrimaryKey }, null_option_type::NOT_NULL);
+  prepare_primary_key(ref, utils::identifier(x));
 }
 
 template<typename Type>
 void attribute_generator::on_attribute(const char *id, Type &/*x*/, const utils::field_attributes &attr) {
-  auto &ref = columns_.emplace_back(id, utils::data_type_traits<Type>::type(attr.size()), attr, null_option_type::NOT_NULL);
-  ref.owner_ = &obj_;
+  std::ignore = emplace_attribute<Type>(id, attr, null_option_type::NOT_NULL);
 }
 
 template<typename Type>
 void attribute_generator::on_attribute(const char *id, std::optional<Type> & /*x*/, const utils::field_attributes &attr) {
-  auto &ref = columns_.emplace_back(id, utils::data_type_traits<Type>::type(attr.size()), attr, null_option_type::NULLABLE);
-  ref.owner_ = &obj_;
+  std::ignore = emplace_attribute<Type>(id, attr, null_option_type::NULLABLE);
 }
 
 }
diff --git a/include/matador/object/basic_object_info.hpp b/include/matador/object/basic_object_info.hpp
index c534402..3a80cc9 100644
--- a/include/matador/object/basic_object_info.hpp
+++ b/include/matador/object/basic_object_info.hpp
@@ -53,6 +53,7 @@ protected:
   basic_object_info(std::shared_ptr<repository_node> node, const std::vector<attribute> &attributes);
 
 protected:
+  std::unique_ptr<object> node_ptr_;
   std::shared_ptr<repository_node> node_;            /**< prototype node of the represented object type */
   std::vector<attribute> attributes_;
   std::optional<utils::identifier> identifier_;
diff --git a/include/matador/object/object.hpp b/include/matador/object/object.hpp
index b33c91f..0168e96 100644
--- a/include/matador/object/object.hpp
+++ b/include/matador/object/object.hpp
@@ -6,6 +6,8 @@
 #include "matador/object/constraint.hpp"
 #include "matador/object/constraints_generator.hpp"
 
+#include "matador/utils/identifier.hpp"
+
 namespace matador::object {
 
 class repository;
@@ -27,6 +29,10 @@ public:
   void add_attribute(attribute attr);
   void add_constraint(class constraint c);
 
+  [[nodiscard]] const attribute* primary_key_attribute() const;
+  [[nodiscard]] const utils::identifier& primary_key() const;
+  [[nodiscard]] bool has_primary_key() const;
+
   [[nodiscard]] const std::string& name() const;
   [[nodiscard]] const std::string& alias() const;
 
@@ -40,10 +46,13 @@ public:
 
 private:
   friend class constraints_generator;
+  friend class attribute_generator;
 
   std::string name_;
   std::string alias_;
 
+  attribute* pk_attribute_{nullptr};
+  utils::identifier pk_identifier_;
   std::vector<attribute> attributes_;
   std::vector<class constraint> constraints_;
 };
diff --git a/source/core/object/attribute_generator.cpp b/source/core/object/attribute_generator.cpp
index c411a56..af22e18 100644
--- a/source/core/object/attribute_generator.cpp
+++ b/source/core/object/attribute_generator.cpp
@@ -1,5 +1,6 @@
 #include "matador/object/attribute_generator.hpp"
 #include "matador/object/repository.hpp"
+#include "matador/object/object.hpp"
 
 namespace matador::object {
 
@@ -21,4 +22,8 @@ void attribute_generator::insert_missing_reference_column(const std::type_index&
   const_cast<repository&>(repo_).missing_references_.insert({ti, ref_column});
 }
 
+void attribute_generator::prepare_primary_key(attribute& ref, utils::identifier &&pk) const {
+  obj_.pk_attribute_ = &ref;
+  obj_.pk_identifier_ = std::move(pk);
+}
 }
\ No newline at end of file
diff --git a/source/core/object/object.cpp b/source/core/object/object.cpp
index a368343..6d53fe8 100644
--- a/source/core/object/object.cpp
+++ b/source/core/object/object.cpp
@@ -21,6 +21,18 @@ void object::add_constraint( class constraint c ) {
   ref.owner_ = this;
 }
 
+const attribute* object::primary_key_attribute() const {
+  return pk_attribute_;
+}
+
+const utils::identifier& object::primary_key() const {
+  return pk_identifier_;
+}
+
+bool object::has_primary_key() const {
+  return pk_attribute_ != nullptr;
+}
+
 const std::string& object::name() const {
   return name_;
 }
diff --git a/test/core/object/ObjectTest.cpp b/test/core/object/ObjectTest.cpp
index ac66eb0..ae69bc3 100644
--- a/test/core/object/ObjectTest.cpp
+++ b/test/core/object/ObjectTest.cpp
@@ -7,14 +7,15 @@
 #include "../test/models/book.hpp"
 
 TEST_CASE("Generate object from type", "[object][generate]") {
-    using namespace matador;
-    object::repository repo;
-    auto result = repo.attach<test::author>("authors");
-    REQUIRE(result);
+  using namespace matador;
+  object::repository repo;
+  auto result = repo.attach<test::author>("authors");
+  REQUIRE(result);
 
-    const auto obj = object::object::generate<test::book>(repo, "books");
-    REQUIRE(obj->name() == "books");
-    REQUIRE(obj->alias().empty());
-    REQUIRE(obj->attributes().size() == 4);
-    REQUIRE(obj->constraints().size() == 2);
+  const auto obj = object::object::generate<test::book>(repo, "books");
+  REQUIRE(obj->name() == "books");
+  REQUIRE(obj->alias().empty());
+  REQUIRE(obj->attributes().size() == 4);
+  REQUIRE(obj->constraints().size() == 2);
+  REQUIRE(obj->has_primary_key());
 }
\ No newline at end of file