DELETE FROM shopping_list WHERE shopping_list_id NOT IN (SELECT id FROM shopping_lists); CREATE TRIGGER remove_items_from_deleted_shopping_list AFTER DELETE ON shopping_lists BEGIN DELETE FROM shopping_list WHERE shopping_list_id = OLD.id; END; CREATE TRIGGER prevent_infinite_nested_recipes_INS BEFORE INSERT ON recipes_nestings BEGIN SELECT CASE WHEN(( SELECT 1 FROM recipes_nestings_resolved rnr WHERE NEW.recipe_id = rnr.includes_recipe_id AND NEW.includes_recipe_id = rnr.recipe_id ) NOTNULL) THEN RAISE(ABORT, "Recursive nested recipe detected") END; END; CREATE TRIGGER prevent_infinite_nested_recipes_UPD BEFORE UPDATE ON recipes_nestings BEGIN SELECT CASE WHEN(( SELECT 1 FROM recipes_nestings_resolved rnr WHERE NEW.recipe_id = rnr.includes_recipe_id AND NEW.includes_recipe_id = rnr.recipe_id ) NOTNULL) THEN RAISE(ABORT, "Recursive nested recipe detected") END; END;