added pk information to class object

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_;
 };