PDO的try / catch的WHERE子句不捕获错误

Question

我使用的是典型的PDO的try / catch子句，和它的作品，因为它应该只是一个方面：WHERE子句。

这里是我的代码：

$pdo->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);

try {
    $cancel_query = "UPDATE table SET active = 0 WHERE id = $request_id";
    $cancel_stmt = $pdo->prepare($cancel_query);
    $cancel_stmt->execute();

    $message = "That request was successfully canceled.";

} catch (PDOException $e) {
    $message = 'This request was not canceled. Something went wrong. ' . $e->getMessage();
}

$pdo = null;

echo $message;

这将捕获错误的大部分时间，例如，如果我故意放错了表名或列名。但是，如果我把一个$ REQUEST_ID不存在，该消息将显示成功。由于没有被更新，因为WHERE子句不拿出一个行更新，这将是在商业意识非常适合将捕捉到的异常。

是否有这样的方式，如果不进行更新，以抛出一个错误？

Answer 1

抛出自己的异常，如果更新未成功完成（或一组$message不同，如果你不想引发异常）

$pdo->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);

try {
    $cancel_query = "UPDATE table SET active = 0 WHERE id = $request_id";
    $cancel_stmt = $pdo->prepare($cancel_query);
    $cancel_stmt->execute();

    if ($cancel_stmt->rowCount() < 1) //Count the number of affected rows, if less than 1 then none
    {
        throw new Exception('Oh no :('); // of course, write a proper error message
        // $message = "something is wrong"; // if you don't want to throw, set $message and use an else statement for the success message
    }
    else
    {
        $message = "That request was successfully canceled.";
    }

} catch (PDOException $e) {
    $message = 'This request was not canceled. Something went wrong. ' . $e->getMessage();
}
catch (Exception $ex)
{
   $message = 'This request was canceled. Something went wrong. ' . $ex->getMessage();
}

$pdo = null;

echo $message;