mysql - 选择查询 Yii2 中的左连接 - 'single' 中的未知列 'on clause'

Question

为什么这个查询不起作用？

public function actionInsert()
{
    $model = new NotificationsEvents();

    $date_at = (new Query())
        ->select(['single-events.date_at'])
        ->from('single-events')
        ->leftJoin('user', 'user.birthday = single-events.date_at');


    $event_id = (new Query())
        ->select(['single-events.id'])
        ->from('single-events')
        ->leftJoin('user', 'user.id = single-events.id');

    (new Query())->createCommand()->insert('notifications_events', [
        'type' => 7,
        'date_at' => $date_at,
        'event_id' => $event_id,
    ])->execute();

}

我需要在 notifications_events.date_at 中插入用户生日，在 notifications_events.event_id 中插入用户 ID，但此代码不起作用:

Unknown column 'single' in 'on clause'

Answer 1

single-events 不是表的有效/安全名称，因为它包含 -。您应该在每个可能的地方引用它:

public function actionInsert() {
    $model = new NotificationsEvents();

    $date_at = (new Query())
        ->select(['{{single-events}}.date_at'])
        ->from('single-events')
        ->leftJoin('user', 'user.birthday = {{single-events}}.date_at');


    $event_id = (new Query())
        ->select(['{{single-events}}.id'])
        ->from('single-events')
        ->leftJoin('user', 'user.id = {{single-events}}.id');

    (new Query())->createCommand()->insert('notifications_events', [
        'type' => 7,
        'date_at' => $date_at,
        'event_id' => $event_id,
    ])->execute();
}

或者为表使用一些更实用的名称，例如single_events。