如果我的 lockForUpdate 返回一个空集，我是否需要回滚/提交？

Question

My code:

$connection->beginTransaction();

$row = $this->newQuery()->where(['someField' => 'someValue'])->lockForUpdate()->get()->first();

if (is_null($row)) {
    $connection->rollBack();

    return null;
}
          
//do some stuff with that row

$connection->commit();

My question: The result is empty, so do I need that rollback? Should I commit? Is transaction still opened by that point?

Answer 1

This is a bug https://bugs.php.net/bug.php?id=76742 in php where deadlock errors were ignored when PDO::ATTR_EMULATE_PREPARES is set to false. This is now fixed in 7.4.13.

Setting PDO::ATTR_EMULATE_PREPARES to true fixes this, ie an error is now thrown when lock wait timeout expires instead of returning an empty result set.

However note that setting PDO::ATTR_EMULATE_PREPARES to true returns all numbers as strings.

You can set this at runtime using.

$connetion->setAttribute(PDO::ATTR_EMULATE_PREPARES,true);