set @front_app_blueprint_exists := (
  select count(1)
  from information_schema.columns
  where table_schema = database()
    and table_name = 'front_project'
    and column_name = 'app_blueprint'
);

set @front_app_blueprint_sql := if(
  @front_app_blueprint_exists = 0,
  'alter table front_project add column app_blueprint longtext comment ''应用蓝图草稿JSON'' after preview_status',
  'select ''front_project.app_blueprint already exists'''
);

prepare front_app_blueprint_stmt from @front_app_blueprint_sql;
execute front_app_blueprint_stmt;
deallocate prepare front_app_blueprint_stmt;