diff --git a/include/matador/sql/column_generator.hpp b/include/matador/sql/column_generator.hpp
index 36f9e4f..f844660 100644
--- a/include/matador/sql/column_generator.hpp
+++ b/include/matador/sql/column_generator.hpp
@@ -27,7 +27,7 @@ public:
   ~column_generator() = default;
 
   template < class Type >
-  static std::vector<column> generate(const object::schema &scm, bool force_lazy = false)
+  static std::vector<column> generate(const object::schema &scm, const bool force_lazy = false)
   {
     const auto info = scm.info<Type>();
     if (!info) {
@@ -36,7 +36,7 @@ public:
     std::vector<column> columns;
     column_generator gen(columns, scm, info.value().get().name(), force_lazy);
     Type obj;
-    matador::access::process(gen, obj);
+    access::process(gen, obj);
     return std::move(columns);
   }
 
@@ -61,10 +61,14 @@ public:
       if (!info) {
         return;
       }
-      table_name_stack_.push(info.value().get().name());
-      typename Pointer::value_type obj;
-      matador::access::process(*this, obj);
-      table_name_stack_.pop();
+      if (seen_tables.count(info->get().name()) == 0) {
+      auto it = seen_tables.insert(info->get().name()).first;
+        table_name_stack_.push(info->get().name());
+        typename Pointer::value_type obj;
+        access::process(*this, obj);
+        table_name_stack_.pop();
+        seen_tables.erase(it);
+      }
     }
   }
   template<class Pointer>
@@ -77,10 +81,14 @@ public:
       if (!info) {
         return;
       }
-      table_name_stack_.push(info.value().get().name());
-      typename Pointer::value_type obj;
-      matador::access::process(*this, obj);
-      table_name_stack_.pop();
+      if (seen_tables.count(info->get().name()) == 0) {
+        auto it = seen_tables.insert(info->get().name()).first;
+        table_name_stack_.push(info.value().get().name());
+        typename Pointer::value_type obj;
+        access::process(*this, obj);
+        table_name_stack_.pop();
+        seen_tables.erase(it);
+      }
     }
   }
   template<class ContainerType>
@@ -94,21 +102,21 @@ public:
       return;
     }
 
-    table_name_stack_.push(info.value().get().name());
-    typename ContainerType::value_type::value_type obj;
-    matador::access::process(*this, obj);
-    table_name_stack_.pop();
+    if (seen_tables.count(info->get().name()) == 0) {
+      auto it = seen_tables.insert(info->get().name()).first;
+      table_name_stack_.push(info.value().get().name());
+      typename ContainerType::value_type::value_type obj;
+      access::process(*this, obj);
+      table_name_stack_.pop();
+      seen_tables.erase(it);
+    }
   }
 
   template<class ContainerType>
-  void on_has_many_to_many(const char *id, ContainerType &c, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes &attr)
-  {
-  }
+  static void on_has_many_to_many(const char *id, ContainerType &c, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes &attr) {}
 
   template<class ContainerType>
-  void on_has_many_to_many(const char *id, ContainerType &c, const utils::foreign_attributes &attr)
-  {
-  }
+  static void on_has_many_to_many(const char *id, ContainerType &c, const utils::foreign_attributes &attr) {}
 
 private:
   void push(const std::string &column_name);
@@ -116,6 +124,7 @@ private:
 private:
   std::stack<std::string> table_name_stack_;
   std::vector<column> &column_infos_;
+  std::unordered_set<std::string> seen_tables;
   const object::schema &table_schema_;
   int column_index{0};
   bool force_lazy_{false};
diff --git a/source/orm/sql/column_generator.cpp b/source/orm/sql/column_generator.cpp
index 8abdb82..03d6468 100644
--- a/source/orm/sql/column_generator.cpp
+++ b/source/orm/sql/column_generator.cpp
@@ -13,6 +13,7 @@ column_generator::column_generator(std::vector<column> &column_infos,
 , force_lazy_(force_lazy)
 {
     table_name_stack_.push(table_name);
+    seen_tables.insert(table_name);
 }
 
 void column_generator::on_primary_key(const char *id, std::string &, size_t)
diff --git a/test/orm/sql/ColumnTest.cpp b/test/orm/sql/ColumnTest.cpp
index 20b69eb..35fd492 100644
--- a/test/orm/sql/ColumnTest.cpp
+++ b/test/orm/sql/ColumnTest.cpp
@@ -11,8 +11,7 @@ TEST_CASE("Test create empty column", "[column]") {
   REQUIRE(c.name() == "name");
   REQUIRE(c.index() == -1);
   REQUIRE(c.type() == basic_type::type_null);
-  REQUIRE(c.reference_column()->table_name().empty());
-  REQUIRE(c.reference_column()->name().empty());
+  REQUIRE(!c.reference_column());
 
   c.set(std::string{"george"}, 255);
   REQUIRE(c.type() == basic_type::type_varchar);
@@ -26,38 +25,47 @@ TEST_CASE("Test create empty column", "[column]") {
 }
 
 TEST_CASE("Test copy and move column", "[column]") {
-  attribute_definition c("name");
+  attribute_definition c(
+    "name",
+    basic_type::type_varchar,
+    2,
+    std::make_shared<attribute_definition>("author", "books", basic_type::type_uint32, constraints::FOREIGN_KEY),
+    constraints::FOREIGN_KEY,
+    null_option::NOT_NULL
+  );
   c.set(std::string{"george"}, 255);
   REQUIRE(c.name() == "name");
-  REQUIRE(c.index() == -1);
-  REQUIRE(c.reference_column()->table_name().empty());
-  REQUIRE(c.reference_column()->name().empty());
+  REQUIRE(c.index() == 2);
+  REQUIRE(c.reference_column());
+  REQUIRE(c.reference_column()->name() == "author");
+  REQUIRE(c.reference_column()->table_name() == "books");
   REQUIRE(c.type() == basic_type::type_varchar);
   REQUIRE(c.as<std::string>() == "george");
   REQUIRE(c.attributes().size() == 255);
 
   auto c2 = c;
   REQUIRE(c2.name() == "name");
-  REQUIRE(c2.index() == -1);
-  REQUIRE(c2.reference_column()->table_name().empty());
-  REQUIRE(c2.reference_column()->name().empty());
+  REQUIRE(c2.index() == 2);
+  REQUIRE(c2.reference_column());
+  REQUIRE(c2.reference_column()->name() == "author");
+  REQUIRE(c2.reference_column()->table_name() == "books");
   REQUIRE(c2.type() == basic_type::type_varchar);
   REQUIRE(c2.as<std::string>() == "george");
   REQUIRE(c2.attributes().size() == 255);
 
   auto c3 = std::move(c2);
   REQUIRE(c3.name() == "name");
-  REQUIRE(c3.index() == -1);
-  REQUIRE(c3.reference_column()->table_name().empty());
-  REQUIRE(c3.reference_column()->name().empty());
+  REQUIRE(c3.index() == 2);
+  REQUIRE(c3.reference_column());
+  REQUIRE(c3.reference_column()->name() == "author");
+  REQUIRE(c3.reference_column()->table_name() == "books");
   REQUIRE(c3.type() == basic_type::type_varchar);
   REQUIRE(c3.as<std::string>() == "george");
   REQUIRE(c3.attributes().size() == 255);
 
   REQUIRE(c2.name().empty());
-  REQUIRE(c2.index() == -1);
-  REQUIRE(c2.reference_column()->table_name().empty());
-  REQUIRE(c2.reference_column()->name().empty());
+  REQUIRE(c2.index() == 2);
+  REQUIRE(!c2.reference_column());
   REQUIRE(c2.type() == basic_type::type_null);
   // REQUIRE(!c2.as<std::string>().has_value());
   REQUIRE(c2.attributes().size() == 255);