php-即使有错误,PDO错误代码也总是00000

我正在运行PHP 7.2.16

不确定启动时,即使有错误,PDO errorCode()或errorInfo()[0]现在总是显示00000

$pdo = new PDO('mysql:host=localhost;dbname=mydb','root','pwd');
$sth = $pdo->prepare('select now() and this is a bad SQL where a - b from c');
$sth->execute();
$row = $sth->fetchAll();
$err = $sth->errorInfo();
echo $sth->errorCode();
print_r($row);
print_r($err);

结果如下：

00000Array
(
)
Array
(
    [0] => 00000
    [1] => 1064
    [2] => You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'a bad SQL where a - b from c' at line 1
)

但是,我只是做了一个新测试,通过删除$sth-> fetchAll()或在此行之前获取错误,可以正确显示：

Array
(
    [0] => 42000
    [1] => 1064
    [2] => You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'a bad SQL where a - b from c' at line 1
)

OK-解决方案是：

get the error code immediately after execute() and before any fetch

最佳答案 我使用PHP 7.1.23测试了以下代码：

$pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES,true);
$sth = $pdo->prepare('select now() and this is a bad SQL where a - b from c');
if ($sth === false) {
  echo "error on prepare()n";
  print_r($pdo->errorInfo());
}
if ($sth->execute() === false) {
  echo "error on execute()n";
  print_r($sth->errorInfo());
}

输出：

error on execute()
Array
(
    [0] => 42000
    [1] => 1064
    [2] => You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'a bad SQL where a - b from c' at line 1
)

然后,我测试了相同的代码,除非禁用了仿真的prepare：

$pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES,false);

输出：

error on prepare()
Array
(
    [0] => 42000
    [1] => 1064
    [2] => You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'a bad SQL where a - b from c' at line 1
)

Fatal error: Uncaught Error: Call to a member function execute() on boolean

故事的道德启示：

>使用模拟的准备好的语句时,prepare()是空操作,并且错误会延迟到execute()为止.我建议禁用模拟的prepare,除非您使用的数据库不支持prepared语句(我不知道任何RDBMS产品的任何当前版本都不能执行真正的prepared语句).
>在prepare()上检查错误时,请使用$pdo-> errorInfo().
>在execute()上检查错误时,请使用$stmt-> errorInfo().

（编辑：衡阳站长网）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!