当设置money字段时，一直报错执行语句返回false，后来改成salary能够成功，但是反复两次执行后又开始缓慢执行，最后还是执行语句报错返回false

<?php

header("content-type:text/html;charset=utf-8");

try{

$options = array(PDO::ATTR_AUTOCOMMIT, 0); //关闭事务的自动提交

$dbh = new PDO('mysql:host=localhost;dbname=test', 'root', '123456');

var_dump($dbh->inTransaction());

//开启事务

$dbh->beginTransaction();

var_dump($dbh->inTransaction());

$sql = "UPDATE userAccount SET salary=salary-1000 WHERE username='king'";

$res1 = $dbh->exec($sql);

var_dump($res1);

if($res1 == 0){

throw new PDOException('king 转账失败！');

}

$res2 = $dbh->exec("UPDATE userAccount SET salary=salary+1000 WHERE username='imooc'");

if($res2 == 0){

throw new PDOException('imooc 接收失败！');

}

$dbh->commit();

}catch(PDOException $e){

//回滚事务

$dbh->rollBack();

echo $e->getMessage();

}