Question

我是PDO SQL查询的新手。我有以下代码，效果很好。当结果只返回1行时，我想将该行设置为valid = FALSE"。我该怎么做？

$sql = "SELECT * FROM `passcodes` WHERE `passcode` = '$passcode' AND `valid` = TRUE";
$stmt = $DBcon->prepare($sql);
$stmt->execute();
$count = $stmt->rowCount();
if($count == 1) {
    //do this
} else {
    //do that
}

Answer 1

又一种解决方案。

IF 您对＆＃34;其他＆＃34;感兴趣上面提到的部分，您可以将@YourCommonSense的优雅解决方案与检查UPDATE中更改的行数相结合。 MySQL返回这样的信息！

$sql = "UPDATE `passcodes` SET `valid` = FALSE WHERE `passcode` = ? AND `valid` = TRUE";
$DBcon->prepare($sql)->execute([$passcode]);
if ($stmt->rowCount() == 0) {
  // do this when nothing found
}

Answer 2

然后我想将该行设置为有效= FALSE“。我该怎么做？

这就是SQL的用途。

$sql = "UPDATE `passcodes` SET `valid` = FALSE WHERE `passcode` = ? AND `valid` = TRUE";
$DBcon->prepare($sql)->execute([$passcode]);

这是您需要的所有代码。

Answer 3

这将适用于等于或大于1的结果行数。我建议使用占位符来准备语句：

$sql = "SELECT `id` FROM `passcodes` WHERE `passcode` = ? AND `valid` = TRUE";
$stmt = $DBcon->prepare($sql);
$stmt->execute([ $passcode ]);
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
if($rows) {
    //do this
    $sql = "UPDATE `passcodes` SET `valid` = FALSE WHERE `id` = ?";
    $stmt = $DBcon->prepare($sql);
    foreach ($rows as $r) {
        $stmt->execute([ $r['id'] ]);
    }
} else {
    //do that
}

来自结果的新SQL PDO查询

3 个答案: