如何使用PHP页面中的shell脚本执行MySQL命令？

要做到这一点,我按照这里显示的方式：https://stackoverflow.com/a/8055745/2117868

这是我的sqlscript.sh

#!/bin/sh
sudo wget -t 50 -O /tmp/update.sql http://example.com/update.sql
if [ $? -eq 0 ]; then
    mysql -h "localhost" -u "root" "-pXXXXXXXX" "database-name" < "/tmp/update.sql"
    if [ $? -eq 0 ]; then
        sudo rm /tmp/update.sql
        echo "200"
    else
        echo "502"
    fi
else
    echo "404"
fi

我的php页面是runscript.php

<?php
    shell_exec("sudo /path/to/script/sqlscript.sh");
?>

现在,当我从服务器控制台或php页面runcript.php调用sqlscript.sh时,它完美地运行并按预期返回200.

但是当我在?/ .my.cnf中使用MYSQL用户和密码时,我根本不需要把它放在命令行上：

[client]
user = root
password = XXXXXXXX

并在sudoer中添加凭据以执行此脚本而无需密码.

User_Alias WWW_USER = www-data
Cmnd_Alias WWW_COMMANDS_SQL = /path/to/script/sqlscript.sh
WWW_USER ALL = (ALL) NOPASSWD: WWW_COMMANDS_SQL

这是我的sqlscript.sh

#!/bin/sh
sudo wget -t 50 -O /tmp/update.sql http://example.com/update.sql
if [ $? -eq 0 ]; then
    mysql -h "localhost" "database-name" < "/tmp/update.sql"
    if [ $? -eq 0 ]; then
        sudo rm /tmp/update.sql
        echo "200"
    else
        echo "502"
    fi
else
    echo "404"
fi

现在,当我从服务器控制台调用sqlscript.sh时,它可以正常工作并按预期返回200.但是如果我从php页面调用它

http://example.com/runscript.php

它返回502,因为它无法执行SQL命令.

更新：

这是Apache error.log

--2014-12-05 10:51:55--  http://example.com/update.sql
Resolving example.com (example.com)... 162.144.71.XXX
Connecting to example.com (example.com)|162.144.71.XXX|:80... connected.
HTTP request sent,awaiting response... 200 OK
Length: 146 [text/x-sql]
Saving to: `/tmp/update.sql'

     0K                                                       100% 10.9M=0s

2014-12-05 10:51:55 (10.9 MB/s) - `/tmp/update.sql' saved [146/146]

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

所以,请帮我解决这个问题.