我正在尝试将排序选项添加到我在Wordpress admin中添加的一些自定义用户列表列中。这是我的代码：

function mmm_user_sortable_columns_query( $userquery ){

    if( \'test_date\' == $userquery -> query_vars[\'orderby\'] ) {

        global $wpdb;

        $userquery -> query_from .= " LEFT OUTER JOIN $wpdb->usermeta AS alias ON ($wpdb->users.ID = alias.user_id) ";
        $userquery -> query_where .= " AND alias.meta_key = \'test_date\' ";
        $userquery -> query_orderby = " ORDER BY alias.meta_value " . ($userquery -> query_vars["order"] == "ASC" ? "asc " : "desc ");

    }

}
add_action( \'pre_user_query\', \'mmm_user_sortable_columns_query\' );

这不能正确排序，因为我的元值不是字符串，而是日期时间。因此，我尝试将query\\u orderby替换为：

$userquery -> query_orderby = " ORDER BY CONVERT( datetime, alias.meta_value ) " . ($userquery -> query_vars["order"] == "ASC" ? "asc " : "desc ");

但这行不通。和添加

$userquery -> query_where .= " AND alias.meta_type = \'DATETIME\' ";

也不行。我错过了什么？

add_action( \'pre_get_users\', function( \\WP_User_Query $q )
{
    $qv = &$q->query_vars;
    if( isset( $qv[\'orderby\'] ) && \'test_date\' === $qv[\'orderby\'] )
    {
        // Custom meta query
        $qv[\'meta_query\'] = [
            \'custom\' => [
                \'key\'   => \'test_date\',
                \'type\'  => \'DATETIME\'
            ]
        ];

        // Order by the \'custom\' meta query
        $qv[\'orderby\'] = \'custom\';

    }
} );