diff --git a/src/model.cpp b/src/model.cpp
index db52ef0..598fc37 100644
--- a/src/model.cpp
+++ b/src/model.cpp
@@ -262,7 +262,8 @@ bool Model::insert_tree(bool insert_whole_tree)
 
 	if( insert_whole_tree )
 	{
-		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_INSERT;
+		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_INSERT;
 		map_fields();
 	}
 
@@ -296,7 +297,8 @@ bool Model::insert_tree(bool insert_whole_tree)
 
 	if( insert_whole_tree )
 	{
-		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_INSERT;
+		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_INSERT;
 		map_fields();
 	}
 
@@ -355,7 +357,8 @@ bool Model::update_tree(bool update_whole_tree)
 
 	if( update_whole_tree )
 	{
-		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_UPDATE;
+		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_UPDATE;
 		map_fields();
 	}
 
@@ -382,7 +385,8 @@ bool Model::update_tree(bool update_whole_tree)
 
 	if( update_whole_tree )
 	{
-		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_UPDATE;
+		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_UPDATE;
 		map_fields();
 	}
 
@@ -441,7 +445,8 @@ bool Model::remove_tree(bool remove_whole_tree)
 
 	if( remove_whole_tree )
 	{
-		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_REMOVE;
+		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_REMOVE;
 		map_fields();
 	}
 
@@ -473,7 +478,8 @@ bool Model::remove_tree(bool remove_whole_tree)
 
 	if( remove_whole_tree )
 	{
-		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_REMOVE;
+		model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_REMOVE;
 		map_fields();
 	}
 
@@ -511,10 +517,11 @@ bool Model::save_tree(bool save_whole_tree)
 	if( save_whole_tree )
 	{
 		if( save_mode == DO_DELETE_ON_SAVE )
-			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_SAVE;
+			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
 		else
-			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_SAVE;
+			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
 
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_SAVE;
 		map_fields();
 	}
 
@@ -544,10 +551,11 @@ bool Model::save_tree(bool save_whole_tree)
 	if( save_whole_tree )
 	{
 		if( save_mode == DO_DELETE_ON_SAVE )
-			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_SAVE;
+			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
 		else
-			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_SAVE;
+			model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
 
+		model_env->model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_SAVE;
 		map_fields();
 	}
 
diff --git a/src/model.h b/src/model.h
index aeec000..2ee6555 100644
--- a/src/model.h
+++ b/src/model.h
@@ -674,6 +674,152 @@ protected:
 protected:
 
 
+	template<typename FieldValue>
+	void field_generic_set_field_value(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
+	{
+		if( model_env->field_value_helper_tab )
+		{
+			if( model_env->field_index >= 0 && (size_t)model_env->field_index < model_env->field_value_helper_tab->size() )
+			{
+				FieldValueHelper & helper = (*model_env->field_value_helper_tab)[model_env->field_index];
+				PT::Log * log = model_connector->get_logger();
+
+				if( is_the_same_field(db_field_name,   helper.db_field_name) &&
+					is_the_same_field(flat_field_name, helper.flat_field_name) )
+				{
+					if( helper.value_object && helper.value_type_info )
+					{
+						if( typeid(field_value) == *helper.value_type_info )
+						{
+							field_value = *(FieldValue*)helper.value_object;
+						}
+						else
+						{
+							table_name(model_env->table_name);
+							(*log) << PT::Log::log1 << "Morm: incorrect type of a field in " << model_env->table_name << ", ";
+
+							if( !is_empty_field(db_field_name) )
+								(*log) << "database field name: " << db_field_name << ", ";
+
+							if( !is_empty_field(flat_field_name) )
+								(*log) << "flat field name: " << flat_field_name << ", ";
+
+							(*log) << "type expected " << typeid(field_value).name()
+								   << " got " << helper.value_type_info->name() << PT::Log::logend;
+						}
+					}
+
+					model_env->field_index += 1;
+				}
+			}
+		}
+	}
+
+	template<typename FieldValue>
+	void field_generic_iterate_primary_key_values(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
+	{
+		if( is_primary_key )
+		{
+			if( model_env->field_value_helper_tab )
+			{
+				if( model_env->field_index >= 0 && (size_t)model_env->field_index < model_env->field_value_helper_tab->size() )
+				{
+					FieldValueHelper & helper = (*model_env->field_value_helper_tab)[model_env->field_index];
+					helper.value_object = &field_value;
+					helper.value_type_info = &typeid(field_value);
+				}
+			}
+
+			model_env->field_index += 1;
+		}
+	}
+
+	template<typename FieldValue>
+	void field_generic_generate_flat_string(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
+	{
+		FlatConnector * flat_connector = model_connector->get_flat_connector();
+
+		if( flat_connector )
+		{
+			FlatExpression * flat_expression = flat_connector->get_expression();
+
+			if( flat_expression && !is_empty_field(flat_field_name) )
+			{
+				// insertable, updatable and is_primary_key are ignored here
+				flat_expression->field(flat_field_name, field_value, insertable, updatable, is_primary_key, model_env);
+			}
+		}
+	}
+
+	template<typename FieldValue>
+	void field_generic_generate_db_sql(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
+	{
+		DbConnector * db_connector = model_connector->get_db_connector();
+
+		if( db_connector )
+		{
+			DbExpression * db_expression = db_connector->get_expression();
+
+			if( db_expression && !is_empty_field(db_field_name) )
+			{
+				db_expression->field(db_field_name, field_value, insertable, updatable, is_primary_key, model_env);
+			}
+		}
+	}
+
+	template<typename FieldValue>
+	void field_generic_read_value_from_db_resultset(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
+	{
+		DbConnector * db_connector = model_connector->get_db_connector();
+
+		if( db_connector )
+		{
+			if( !is_empty_field(db_field_name) )
+			{
+				if( model_env->cursor_helper && model_env->cursor_helper->has_autogenerated_select )
+				{
+					get_value_by_field_index(model_env->cursor_helper->current_column, field_value);
+					model_env->cursor_helper->current_column += 1;
+				}
+				else
+				{
+					get_value_by_field_name(db_field_name, field_value);
+				}
+			}
+		}
+	}
+
+	template<typename FieldValue>
+	void field_generic_clear_value(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
+	{
+		Clearer * clearer = model_connector->get_clearer();
+
+		if( clearer )
+		{
+			clearer->clear_value(field_value);
+		}
+	}
+
+	// will be changed
+	template<typename FieldValue>
+	void field_generic_generate_doc_for_flat(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
+	{
+		FlatConnector * doc_connector = model_connector->get_doc_connector(); // different connector will be here (doc, flat)
+
+		if( doc_connector )
+		{
+			FlatExpression * doc_expression = doc_connector->get_expression();
+
+			// potrzebujemy dwa rozne doce, jeden dla flat drugi dla bazy danych
+			if( doc_expression && !is_empty_field(flat_field_name) )
+			{
+				// insertable, updatable and is_primary_key are ignored here
+				doc_expression->field_doc(*this, flat_field_name, field_value, insertable, updatable, is_primary_key, model_env);
+			}
+		}
+	}
+
+
 	template<typename FieldValue>
 	void field_generic(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValue & field_value, bool insertable, bool updatable, bool is_primary_key)
 	{
@@ -681,137 +827,37 @@ protected:
 		{
 			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_SET_FIELD_VALUE )
 			{
-				if( model_env->field_value_helper_tab )
-				{
-					if( model_env->field_index >= 0 && (size_t)model_env->field_index < model_env->field_value_helper_tab->size() )
-					{
-						FieldValueHelper & helper = (*model_env->field_value_helper_tab)[model_env->field_index];
-						PT::Log * log = model_connector->get_logger();
-
-						if( is_the_same_field(db_field_name,   helper.db_field_name) &&
-							is_the_same_field(flat_field_name, helper.flat_field_name) )
-						{
-							if( helper.value_object && helper.value_type_info )
-							{
-								if( typeid(field_value) == *helper.value_type_info )
-								{
-									field_value = *(FieldValue*)helper.value_object;
-								}
-								else
-								{
-									table_name(model_env->table_name);
-									(*log) << PT::Log::log1 << "Morm: incorrect type of a field in " << model_env->table_name << ", ";
-
-									if( !is_empty_field(db_field_name) )
-										(*log) << "database field name: " << db_field_name << ", ";
-
-									if( !is_empty_field(flat_field_name) )
-										(*log) << "flat field name: " << flat_field_name << ", ";
-
-									(*log) << "type expected " << typeid(field_value).name()
-										   << " got " << helper.value_type_info->name() << PT::Log::logend;
-								}
-							}
-
-							model_env->field_index += 1;
-						}
-					}
-				}
+				field_generic_set_field_value(db_field_name, flat_field_name, field_value, insertable, updatable, is_primary_key);
 			}
 
-			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_PRIMARY_KEY_VALUES && is_primary_key )
+			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_PRIMARY_KEY_VALUES )
 			{
-				if( model_env->field_value_helper_tab )
-				{
-					if( model_env->field_index >= 0 && (size_t)model_env->field_index < model_env->field_value_helper_tab->size() )
-					{
-						FieldValueHelper & helper = (*model_env->field_value_helper_tab)[model_env->field_index];
-						helper.value_object = &field_value;
-						helper.value_type_info = &typeid(field_value);
-					}
-				}
-
-				model_env->field_index += 1;
+				field_generic_iterate_primary_key_values(db_field_name, flat_field_name, field_value, insertable, updatable, is_primary_key);
 			}
 
-
 			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_GENERATING_FLAT_STRING )
 			{
-				FlatConnector * flat_connector = model_connector->get_flat_connector();
-
-				if( flat_connector )
-				{
-					FlatExpression * flat_expression = flat_connector->get_expression();
-
-					if( flat_expression && !is_empty_field(flat_field_name) )
-					{
-						// insertable, updatable and is_primary_key are ignored here
-						flat_expression->field(flat_field_name, field_value, insertable, updatable, is_primary_key, model_env);
-					}
-				}
+				field_generic_generate_flat_string(db_field_name, flat_field_name, field_value, insertable, updatable, is_primary_key);
 			}
 
 			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_GENERATING_DB_SQL )
 			{
-				DbConnector * db_connector = model_connector->get_db_connector();
-
-				if( db_connector )
-				{
-					DbExpression * db_expression = db_connector->get_expression();
-
-					if( db_expression && !is_empty_field(db_field_name) )
-					{
-						db_expression->field(db_field_name, field_value, insertable, updatable, is_primary_key, model_env);
-					}
-				}
+				field_generic_generate_db_sql(db_field_name, flat_field_name, field_value, insertable, updatable, is_primary_key);
 			}
 
 			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_READING_VALUE_FROM_DB_RESULTSET )
 			{
-				DbConnector * db_connector = model_connector->get_db_connector();
-
-				if( db_connector )
-				{
-					if( !is_empty_field(db_field_name) )
-					{
-						if( model_env->cursor_helper && model_env->cursor_helper->has_autogenerated_select )
-						{
-							get_value_by_field_index(model_env->cursor_helper->current_column, field_value);
-							model_env->cursor_helper->current_column += 1;
-						}
-						else
-						{
-							get_value_by_field_name(db_field_name, field_value);
-						}
-					}
-				}
+				field_generic_read_value_from_db_resultset(db_field_name, flat_field_name, field_value, insertable, updatable, is_primary_key);
 			}
 
 			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_CLEARING_VALUE )
 			{
-				Clearer * clearer = model_connector->get_clearer();
-
-				if( clearer )
-				{
-					clearer->clear_value(field_value);
-				}
+				field_generic_clear_value(db_field_name, flat_field_name, field_value, insertable, updatable, is_primary_key);
 			}
 
 			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_GENERATING_DOC_FOR_FLAT )
 			{
-				FlatConnector * doc_connector = model_connector->get_doc_connector(); // different connector will be here (doc, flat)
-
-				if( doc_connector )
-				{
-					FlatExpression * doc_expression = doc_connector->get_expression();
-
-					// potrzebujemy dwa rozne doce, jeden dla flat drugi dla bazy danych
-					if( doc_expression && !is_empty_field(flat_field_name) )
-					{
-						// insertable, updatable and is_primary_key are ignored here
-						doc_expression->field_doc(*this, flat_field_name, field_value, insertable, updatable, is_primary_key, model_env);
-					}
-				}
+				field_generic_generate_doc_for_flat(db_field_name, flat_field_name, field_value, insertable, updatable, is_primary_key);
 			}
 		}
 	}
@@ -882,6 +928,104 @@ protected:
 	}
 
 
+	void field_model_set_parent_key(const wchar_t * db_field_name, const wchar_t * flat_field_name, Model & field_model)
+	{
+		DbConnector * db_connector = model_connector->get_db_connector();
+		PT::Log * log = model_connector->get_logger();
+
+		if( db_connector )
+		{
+			DbExpression * db_expression = db_connector->get_expression();
+
+			if( db_expression && !is_empty_field(db_field_name) )
+			{
+				int old_connector_mode = model_env->model_connector_mode;
+				model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_PRIMARY_KEY_VALUES;
+
+				FieldValueHelper helper; // in the future we can have a primary key from more than one column
+				helper.db_field_name = db_field_name;
+				helper.flat_field_name = flat_field_name;
+
+				std::vector<FieldValueHelper> helper_tab;
+				helper_tab.push_back(helper);
+
+				model_env->field_value_helper_tab = &helper_tab;
+				model_env->field_index = 0;
+
+				/*
+				 * first we iterate through fields and save primary key values to helper_tab
+				 */
+				map_fields();
+
+				if( (size_t)model_env->field_index == helper_tab.size() )
+				{
+					ModelEnv model_env_local;
+					model_env_local.copy_global_objects(*model_env);
+					model_env_local.model_connector_mode = MORM_MODEL_CONNECTOR_MODE_SET_FIELD_VALUE;
+					model_env_local.field_value_helper_tab = &helper_tab;
+					model_env_local.field_index = 0;
+					field_model.model_env = &model_env_local;
+
+					/*
+					 * now we iterate through fields in field_model and save primary key values from *this object to the specified fields in field_model
+					 */
+					field_model.map_fields();
+
+					if( (size_t)field_model.model_env->field_index != helper_tab.size() && log )
+					{
+						table_name(model_env->table_name);
+						field_model.table_name(field_model.model_env->table_name);
+
+						(*log) << PT::Log::log1 << "Morm: primary key in " << model_env->table_name << " consists of " << model_env->field_index << " column(s)"
+							   << " but in " << field_model.model_env->table_name << " there are only "
+							   << field_model.model_env->field_index << " matching column(s)" << PT::Log::logend;
+					}
+
+					field_model.model_env = nullptr;
+				}
+				else
+				if( log )
+				{
+					table_name(model_env->table_name);
+
+					(*log) << PT::Log::log1 << "Morm: primary key in " << model_env->table_name << " consists of incorrect number of columns"
+						   << ", expected " << helper_tab.size() << " column(s) but got " << model_env->field_index << PT::Log::logend;
+				}
+
+				model_env->field_value_helper_tab = nullptr;
+				model_env->model_connector_mode = old_connector_mode;
+			}
+		}
+	}
+
+
+	void field_model_iterate_through_childs(const wchar_t * db_field_name, Model & field_model)
+	{
+		if( !is_empty_field(db_field_name) )
+		{
+			if( model_env->model_connector_submode == MORM_MODEL_CONNECTOR_SUBMODE_INSERT )
+			{
+				field_model.insert_tree(true);
+			}
+
+			if( model_env->model_connector_submode == MORM_MODEL_CONNECTOR_SUBMODE_UPDATE )
+			{
+				field_model.update_tree(true);
+			}
+
+			if( model_env->model_connector_submode == MORM_MODEL_CONNECTOR_SUBMODE_REMOVE )
+			{
+				field_model.remove_tree(true);
+			}
+
+			if( model_env->model_connector_submode == MORM_MODEL_CONNECTOR_SUBMODE_SAVE )
+			{
+				field_model.save_tree(true);
+			}
+		}
+	}
+
+
 
 	void field_model_generate_flat_string(const wchar_t * db_field_name, const wchar_t * flat_field_name, Model & field_model, bool insertable, bool updatable)
 	{
@@ -1031,77 +1175,6 @@ protected:
 		}
 	}
 
-	void field_model_set_parent_key(const wchar_t * db_field_name, const wchar_t * flat_field_name, Model & field_model)
-	{
-		DbConnector * db_connector = model_connector->get_db_connector();
-		PT::Log * log = model_connector->get_logger();
-
-		if( db_connector )
-		{
-			DbExpression * db_expression = db_connector->get_expression();
-
-			if( db_expression && !is_empty_field(db_field_name) )
-			{
-				int old_connector_mode = model_env->model_connector_mode;
-				model_env->model_connector_mode = MORM_MODEL_CONNECTOR_MODE_ITERATE_PRIMARY_KEY_VALUES;
-
-				FieldValueHelper helper; // in the future we can have a primary key from more than one column
-				helper.db_field_name = db_field_name;
-				helper.flat_field_name = flat_field_name;
-
-				std::vector<FieldValueHelper> helper_tab;
-				helper_tab.push_back(helper);
-
-				model_env->field_value_helper_tab = &helper_tab;
-				model_env->field_index = 0;
-
-				/*
-				 * first we iterate through fields and save primary key values to helper_tab
-				 */
-				map_fields();
-
-				if( (size_t)model_env->field_index == helper_tab.size() )
-				{
-					ModelEnv model_env_local;
-					model_env_local.copy_global_objects(*model_env);
-					model_env_local.model_connector_mode = MORM_MODEL_CONNECTOR_MODE_SET_FIELD_VALUE;
-					model_env_local.field_value_helper_tab = &helper_tab;
-					model_env_local.field_index = 0;
-					field_model.model_env = &model_env_local;
-
-					/*
-					 * now we iterate through fields in field_model and save primary key values from *this object to the specified fields in field_model
-					 */
-					field_model.map_fields();
-
-					if( (size_t)field_model.model_env->field_index != helper_tab.size() && log )
-					{
-						table_name(model_env->table_name);
-						field_model.table_name(field_model.model_env->table_name);
-
-						(*log) << PT::Log::log1 << "Morm: primary key in " << model_env->table_name << " consists of " << model_env->field_index << " column(s)"
-							   << " but in " << field_model.model_env->table_name << " there are only "
-							   << field_model.model_env->field_index << " matching column(s)" << PT::Log::logend;
-					}
-
-					field_model.model_env = nullptr;
-				}
-				else
-				if( log )
-				{
-					table_name(model_env->table_name);
-
-					(*log) << PT::Log::log1 << "Morm: primary key in " << model_env->table_name << " consists of incorrect number of columns"
-						   << ", expected " << helper_tab.size() << " column(s) but got " << model_env->field_index << PT::Log::logend;
-				}
-
-				model_env->field_value_helper_tab = nullptr;
-				model_env->model_connector_mode = old_connector_mode;
-			}
-		}
-	}
-
-
 	void field_model(const wchar_t * db_field_name, const wchar_t * flat_field_name, Model & field_model, bool insertable, bool updatable, bool has_foreign_key)
 	{
 		if( model_connector && model_env )
@@ -1112,51 +1185,27 @@ protected:
 			field_model.model_env = &model_env_local;
 			field_model.set_connector(model_connector);
 
-			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_SET_PARENT_ID && !has_foreign_key )
+			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_SET_PARENT_ID )
 			{
-				field_model_set_parent_key(db_field_name, flat_field_name, field_model);
+				if( !has_foreign_key )
+				{
+					field_model_set_parent_key(db_field_name, flat_field_name, field_model);
+				}
 			}
 
-			if( !is_empty_field(db_field_name) )
+			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY )
 			{
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_INSERT && has_foreign_key )
+				if( has_foreign_key )
 				{
-					field_model.insert_tree(true);
+					field_model_iterate_through_childs(db_field_name, field_model);
 				}
+			}
 
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_INSERT && !has_foreign_key )
+			if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY )
+			{
+				if( !has_foreign_key )
 				{
-					field_model.insert_tree(true);
-				}
-
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_UPDATE && has_foreign_key )
-				{
-					field_model.update_tree(true);
-				}
-
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_UPDATE && !has_foreign_key )
-				{
-					field_model.update_tree(true);
-				}
-
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_REMOVE && has_foreign_key )
-				{
-					field_model.remove_tree(true);
-				}
-
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_REMOVE && !has_foreign_key )
-				{
-					field_model.remove_tree(true);
-				}
-
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_SAVE && has_foreign_key )
-				{
-					field_model.save_tree(true);
-				}
-
-				if( model_env->model_connector_mode == MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_SAVE && !has_foreign_key )
-				{
-					field_model.save_tree(true);
+					field_model_iterate_through_childs(db_field_name, field_model);
 				}
 			}
 
diff --git a/src/modelenv.h b/src/modelenv.h
index 3f9e26c..a6ba1b1 100644
--- a/src/modelenv.h
+++ b/src/modelenv.h
@@ -56,6 +56,7 @@ public:
 	FinderHelper * finder_helper;
 	CursorHelper * cursor_helper;
 	int model_connector_mode;
+	int model_connector_submode;
 	bool dump_mode;
 
 	// local objects
@@ -89,6 +90,7 @@ public:
 		finder_helper = e.finder_helper;
 		cursor_helper = e.cursor_helper;
 		model_connector_mode = e.model_connector_mode;
+		model_connector_submode = e.model_connector_submode;
 		dump_mode = e.dump_mode;
 		table_index = e.table_index;
 		doc_field_pointer = e.doc_field_pointer;
@@ -108,6 +110,7 @@ public:
 		cursor_helper = e.cursor_helper;
 
 		model_connector_mode = e.model_connector_mode;
+		model_connector_submode = e.model_connector_submode;
 		dump_mode = e.dump_mode;
 
 		// what about doc_field_pointer?
@@ -119,6 +122,7 @@ public:
 		finder_helper = nullptr;
 		cursor_helper = nullptr;
 		model_connector_mode = MORM_MODEL_CONNECTOR_MODE_NONE;
+		model_connector_submode = MORM_MODEL_CONNECTOR_SUBMODE_NONE;
 		dump_mode = false;
 		doc_field_pointer = nullptr;
 		table_name.clear();
diff --git a/src/morm_types.h b/src/morm_types.h
index 050f693..fab2d49 100644
--- a/src/morm_types.h
+++ b/src/morm_types.h
@@ -47,24 +47,20 @@
 #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_WITH_FOREIGN_KEY 8
+#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY 9
 
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_INSERT 8
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_INSERT 9
+#define MORM_MODEL_CONNECTOR_MODE_SET_PARENT_ID 10
+#define MORM_MODEL_CONNECTOR_MODE_ITERATE_PRIMARY_KEY_VALUES 11
+#define MORM_MODEL_CONNECTOR_MODE_SET_FIELD_VALUE 12
 
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_UPDATE 10
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_UPDATE 11
 
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_SAVE 12
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_SAVE 13
-
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY_AND_REMOVE 14
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY_AND_REMOVE 15
-
-#define MORM_MODEL_CONNECTOR_MODE_SET_PARENT_ID 16
-
-#define MORM_MODEL_CONNECTOR_MODE_ITERATE_PRIMARY_KEY_VALUES 17
-
-#define MORM_MODEL_CONNECTOR_MODE_SET_FIELD_VALUE 18
+// submodes used in some cases
+#define MORM_MODEL_CONNECTOR_SUBMODE_NONE 0
+#define MORM_MODEL_CONNECTOR_SUBMODE_INSERT 1
+#define MORM_MODEL_CONNECTOR_SUBMODE_UPDATE 2
+#define MORM_MODEL_CONNECTOR_SUBMODE_REMOVE 3
+#define MORM_MODEL_CONNECTOR_SUBMODE_SAVE 4