Mysql 如何在创建插件时在wordpress中编写删除级联

Mysql 如何在创建插件时在wordpress中编写删除级联,mysql,database,wordpress,Mysql,Database,Wordpress,在我的WordPress插件中创建数据库时,我想写关于删除级联和更新级联的内容 public function create_table(){ global $wpdb; require_once (ABSPATH.'wp-admin/includes/upgrade.php'); $ps_detail_table_name = $wpdb->prefix.'ps_details'; $ps_category_table_name = $wpdb->

在我的WordPress插件中创建数据库时,我想写关于删除级联和更新级联的内容

public function create_table(){
    global $wpdb;

    require_once (ABSPATH.'wp-admin/includes/upgrade.php');

    $ps_detail_table_name = $wpdb->prefix.'ps_details';
    $ps_category_table_name = $wpdb->prefix.'ps_category';
    $ps_type_table_name = $wpdb->prefix.'ps_type';

    $ps_detail_sql = "CREATE TABLE IF NOT EXISTS ".$ps_detail_table_name."(
                      id int(11) NOT NULL AUTO_INCREMENT,
                      category VARCHAR(255) NOT NULL,
                      type VARCHAR(255) NULL,
                      image_path VARCHAR(255) NOT NULL,
                      name VARCHAR(255) NOT NULL,
                      description VARCHAR(255) NOT NULL,
                      PRIMARY KEY (id),
                      FOREIGN KEY (type) REFERENCES ".$ps_type_table_name."(type)
                      ON DELETE CASCADE
                      ON UPDATE CASCADE 
                      )";
    dbDelta($ps_detail_sql);

    $ps_category_sql = "CREATE TABLE IF NOT EXISTS ".$ps_category_table_name."(
                      id int(11) NOT NULL AUTO_INCREMENT,
                      category VARCHAR(255) NOT NULL,
                      PRIMARY KEY (id))";
    dbDelta($ps_category_sql);

    $ps_type_sql = "CREATE TABLE IF NOT EXISTS ".$ps_type_table_name."(
                      id int(11) NOT NULL AUTO_INCREMENT,
                      category VARCHAR(255) NOT NULL,
                      type VARCHAR(255) NULL,
                      PRIMARY KEY (id))";
    dbDelta($ps_type_sql);

}
这是我的代码,如果我删除了DELETE CASCADE和UPDATE CASCADE,它就会工作,如果它在那里,那么除了包含CASCADE的表之外,还会创建另外两个表。我该怎么解决这个问题