MySQL“等待超时"长时间查询不被尊重?

I'm trying to test the wait_timeout MySQL setting which seems to be ignored.

PHP 脚本:

<?php
function microtime_float()
{
    list($usec, $sec) = explode(" ", microtime());
    return ((float)$usec + (float)$sec);
}

$sql = mysqli_connect('localhost','root','root','mysql');
$query = "SHOW VARIABLES WHERE Variable_name='wait_timeout';";
$result = $sql->query($query) or die($query.'<br />'.$sql->error);
$row = $result->fetch_object();
echo "wait_timeout = " . $row->Value . "<br/>
";

$time_start = microtime_float();
$query = "SELECT SLEEP(2) FROM mysql.user;";
$sql->query($query) or die($query.'<br />'.$sql->error);
$time_end = microtime_float();
$time = $time_end - $time_start;
echo "Query completed in $time seconds<br/>
";
echo "You got the page";

脚本输出:

wait_timeout = 2
Query completed in 8.0005459785461 seconds
You got the page

我的配置

mariadb-server-5.3.5
php5.3.6

我需要做什么才能强制 MySQL 在一定时间后超时查询?

推荐答案

wait_timeout 和 interactive_timeout 都是断开连接之前不活动的时间.因此，连接必须处于空闲状态(不运行查询)才能被丢弃.MySQL SLEEP() 不算数，因为您正在运行查询.