diff --git a/samples/language.h b/samples/language.h
index f1a962f..4fa2088 100644
--- a/samples/language.h
+++ b/samples/language.h
@@ -84,6 +84,10 @@ public:
 		stream << "public.language";
 	}
 
+	void after_insert()
+	{
+		get_last_sequence(L"public.language_id_seq", id);
+	}
 
 
 };
diff --git a/samples/person.h b/samples/person.h
index c0496aa..7e4f1fb 100644
--- a/samples/person.h
+++ b/samples/person.h
@@ -83,6 +83,10 @@ public:
 		stream << "public.person";
 	}
 
+	void after_insert()
+	{
+		get_last_sequence(L"public.person_id_seq", id);
+	}
 
 
 };
diff --git a/src/dbconnector.cpp b/src/dbconnector.cpp
index 5ec5569..c1ac2cb 100644
--- a/src/dbconnector.cpp
+++ b/src/dbconnector.cpp
@@ -187,7 +187,7 @@ void DbConnector::generate_insert_query(PT::TextStream & stream, Model & model)
 
 		stream << " (";
 		db_expression->set_work_mode(MORM_WORK_MODE_MODEL_FIELDS);
-		db_expression->set_output_type(MORM_OUTPUT_TYPE_DB_UPDATE);
+		db_expression->set_output_type(MORM_OUTPUT_TYPE_DB_INSERT);
 		db_expression->generate_from_model(stream, model);
 
 		stream << ") values (";
diff --git a/src/dbexpression.cpp b/src/dbexpression.cpp
index c489b7f..fb8ba48 100644
--- a/src/dbexpression.cpp
+++ b/src/dbexpression.cpp
@@ -74,7 +74,9 @@ bool DbExpression::can_field_be_generated(bool insertable, bool updatable, bool
 		return updatable;
 	}
 	else
-	if( output_type == MORM_OUTPUT_TYPE_DB_PRIMARY_KEY || output_type == MORM_OUTPUT_TYPE_JOIN_TABLES )
+	if( output_type == MORM_OUTPUT_TYPE_DB_PRIMARY_KEY ||
+		output_type == MORM_OUTPUT_TYPE_JOIN_TABLES ||
+		output_type == MORM_OUTPUT_TYPE_DB_INSERT_PRIMARY_KEY )
 	{
 		return is_primary_key;
 	}
@@ -104,6 +106,11 @@ void DbExpression::field_before()
 			(*out_stream) << " AND ";
 		}
 		else
+		if( output_type == MORM_OUTPUT_TYPE_DB_INSERT_PRIMARY_KEY )
+		{
+			(*out_stream) << ", ";
+		}
+		else
 		if( output_type == MORM_OUTPUT_TYPE_WHERE_EQ ||
 			output_type == MORM_OUTPUT_TYPE_WHERE_GE ||
 			output_type == MORM_OUTPUT_TYPE_WHERE_GT ||
diff --git a/src/model.cpp b/src/model.cpp
index b670279..e8ce949 100644
--- a/src/model.cpp
+++ b/src/model.cpp
@@ -232,17 +232,29 @@ void Model::generate_insert_query(PT::TextStream & stream, ModelData * model_dat
 }
 
 
+bool Model::insert(ModelData * model_data, bool insert_whole_tree)
+{
+	ModelEnv model_env_local;
+	model_env = &model_env_local;
 
-bool Model::insert(ModelData * model_data)
+	model_env->model_data = model_data;
+	return insert_tree(insert_whole_tree);
+}
+
+
+// has ModelEnv set
+bool Model::insert_tree(bool insert_whole_tree)
 {
 	bool result = false;
 
+	if( insert_whole_tree )
+	{
+		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_AND_INSERT;
+		map_fields();
+	}
+
 	if( model_connector )
 	{
-		ModelEnv model_env_local;
-		model_env = &model_env_local;
-
-		model_env->model_data = model_data;
 		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_GENERATING_DB_SQL;
 		DbConnector * db_connector = model_connector->get_db_connector();
 
@@ -251,6 +263,7 @@ bool Model::insert(ModelData * model_data)
 
 		if( db_connector && out_stream )
 		{
+
 			before_insert();
 			out_stream->clear();
 			result = db_connector->insert(*out_stream, *this);
@@ -275,9 +288,9 @@ bool Model::insert(ModelData * model_data)
 
 
 
-bool Model::insert(ModelData & model_data)
+bool Model::insert(ModelData & model_data, bool insert_whole_tree)
 {
-	return insert(&model_data);
+	return insert(&model_data, insert_whole_tree);
 }
 
 
diff --git a/src/model.h b/src/model.h
index a5d7442..e0a99bd 100644
--- a/src/model.h
+++ b/src/model.h
@@ -110,8 +110,8 @@ public:
 	virtual std::string to_string();
 
 	virtual void generate_insert_query(PT::TextStream & stream, ModelData * model_data = nullptr);
-	virtual bool insert(ModelData * model_data = nullptr);
-	virtual bool insert(ModelData & model_data);
+	virtual bool insert(ModelData * model_data = nullptr, bool insert_whole_tree = true);
+	virtual bool insert(ModelData & model_data, bool insert_whole_tree = true);
 
 	virtual void generate_update_query(PT::TextStream & stream, ModelData * model_data = nullptr);
 	virtual bool update(ModelData * model_data = nullptr);
@@ -165,6 +165,7 @@ protected:
 
 	virtual ModelData * get_model_data();
 
+	virtual bool insert_tree(bool insert_whole_tree);
 
 	virtual void map_values_from_query();
 
@@ -826,6 +827,19 @@ protected:
 					field_model_left_join(db_field_name, flat_field_name, field_model, insertable, updatable, has_foreign_key, db_expression);
 				}
 
+				if( db_expression->get_work_mode() == MORM_WORK_MODE_MODEL_FIELDS && db_expression->get_output_type() == MORM_OUTPUT_TYPE_DB_INSERT )
+				{
+					int not_used_object = 0;
+					db_expression->field(db_field_name, not_used_object, insertable, updatable, false, model_env);
+				}
+
+				if( db_expression->get_work_mode() == MORM_WORK_MODE_MODEL_VALUES && db_expression->get_output_type() == MORM_OUTPUT_TYPE_DB_INSERT )
+				{
+					db_expression->set_output_type(MORM_OUTPUT_TYPE_DB_INSERT_PRIMARY_KEY);
+					field_model.map_fields();
+					db_expression->set_output_type(MORM_OUTPUT_TYPE_DB_INSERT);
+				}
+
 				if( db_expression->get_output_type() != MORM_OUTPUT_TYPE_JOIN_TABLES &&
 					db_expression->get_output_type() != MORM_OUTPUT_TYPE_DB_INSERT &&
 					db_expression->get_output_type() != MORM_OUTPUT_TYPE_DB_UPDATE )
@@ -899,6 +913,27 @@ protected:
 			field_model.model_env = &model_env_local;
 			field_model.set_connector(model_connector);
 
+			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_AND_INSERT )
+			{
+				// IMPROVE ME what about if db_field_name is empty? not iterate in such a case?
+				field_model.map_fields();
+				field_model.insert_tree(true);
+			}
+
+			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_AND_UPDATE )
+			{
+				// IMPROVE ME what about if db_field_name is empty? not iterate in such a case?
+				//field_model.map_fields();
+				//field_model.update_tree(true);
+			}
+
+			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_AND_SAVE )
+			{
+				// IMPROVE ME what about if db_field_name is empty? not iterate in such a case?
+				//field_model.map_fields();
+				//field_model.save_tree(true);
+			}
+
 			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_GENERATING_FLAT_STRING )
 			{
 				field_model_generate_flat_string(db_field_name, flat_field_name, field_model, insertable, updatable);
diff --git a/src/morm_types.h b/src/morm_types.h
index d1a2c61..2fc65da 100644
--- a/src/morm_types.h
+++ b/src/morm_types.h
@@ -47,6 +47,9 @@
 #define MORM_MODEL_CONNECTOR_MODE_READING_VALUE_FROM_DB_RESULTSET 6
 #define MORM_MODEL_CONNECTOR_MODE_CLEARING_VALUE 7
 
+#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_AND_INSERT 8
+#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_AND_UPDATE 9
+#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_AND_SAVE 10
 
 
 #define MORM_WORK_MODE_MODEL_FIELDS 1
@@ -66,10 +69,13 @@
 // change to something like MORM_OUTPUT_TYPE_DB_WHERE_PRIMARY_KEY
 #define MORM_OUTPUT_TYPE_DB_PRIMARY_KEY 4
 
-//#define MORM_OUTPUT_TYPE_WHERE_CUSTOM 5
-#define MORM_OUTPUT_TYPE_SELECT_COLUMNS 6
+#define MORM_OUTPUT_TYPE_DB_INSERT_PRIMARY_KEY 5
 
-#define MORM_OUTPUT_TYPE_JOIN_TABLES 7
+
+//#define MORM_OUTPUT_TYPE_WHERE_CUSTOM 6
+#define MORM_OUTPUT_TYPE_SELECT_COLUMNS 7
+
+#define MORM_OUTPUT_TYPE_JOIN_TABLES 8
 
 #define MORM_OUTPUT_TYPE_WHERE_EQ 10
 #define MORM_OUTPUT_TYPE_WHERE_LT 11