text: /**
   * Database schema required by \yii\rbac\DbManager.
   *
   * @author Qiang Xue <qiang.xue@gmail.com>
   * @author Alexander Kochetov <creocoder@gmail.com>
   * @link http://www.yiiframework.com/
   * @copyright 2008 Yii Software LLC
   * @license http://www.yiiframework.com/license/
   * @since 2.0
   */
  
  drop table if exists `auth_assignment`;
  drop table if exists `auth_item_child`;
  drop table if exists `auth_item`;
  drop table if exists `auth_rule`;
  
  create table `auth_rule`
  (
     `name`                 varchar(64) not null,
     `data`                 blob,
     `created_at`           integer,
     `updated_at`           integer,
      primary key (`name`)
  ) engine InnoDB;
  
  create table `auth_item`
  (
     `name`                 varchar(64) not null,
     `type`                 smallint not null,
     `description`          text,
     `rule_name`            varchar(64),
     `data`                 blob,
     `created_at`           integer,
     `updated_at`           integer,
     primary key (`name`),
     foreign key (`rule_name`) references `auth_rule` (`name`) on delete set null on update cascade,
     key `type` (`type`)
  ) engine InnoDB;
  
  create table `auth_item_child`
  (
     `parent`               varchar(64) not null,
     `child`                varchar(64) not null,
     primary key (`parent`, `child`),
     foreign key (`parent`) references `auth_item` (`name`) on delete cascade on update cascade,
     foreign key (`child`) references `auth_item` (`name`) on delete cascade on update cascade
  ) engine InnoDB;
  
  create table `auth_assignment`
  (
     `item_name`            varchar(64) not null,
     `user_id`              varchar(64) not null,
     `created_at`           integer,
     primary key (`item_name`, `user_id`),
     foreign key (`item_name`) references `auth_item` (`name`) on delete cascade on update cascade
  ) engine InnoDB;
  