MySQL常见错误及解决方案:PHP兼容性与密码验证问题

栏目:技术文章 发布时间:2026-04-16 09:24
文章重点分析MySQL程序使用中频发的错误类型,发现PHP旧版mysql扩展与MySQL 4.1+存在协议兼容问题,需通过调整MySQL配置解决。mysqli扩展可直接支持新密码哈希机制,而TCP/IP连接异常、包大小限制及表满错误等需针对性排查硬件

Common Errors When Using MySQL Programs

Note: In older versions of PHP, the mysql extension does not support the authentication protocol in MySQL 4.1.1 and higher. This is true regardless of the PHP version being used. If you wish to use the mysql extension with MySQL 4.1 or newer, you may need to follow one of the options discussed above for configuring MySQL to work with old clients. The mysqli extension (stands for "MySQL, Improved"; added in PHP 5) is compatible with the improved password hashing employed in MySQL 4.1 and higher, and no special configuration of MySQL need be done in order to use this MySQL client library. For more information about the mysqli extension, see http://php.net/mysqli.

For additional background on password hashing and authentication, see Section 5.7.9, “Password Hashing in MySQL 4.1”.

4. Password Fails When Entered Interactively

Badly configured TCP/IP.

Faulty Ethernets, hubs, switches, cables, and so forth. This can be diagnosed properly only by replacing hardware.

MySQL常见错误及解决方案:PHP兼容性与密码验证问题(图1)

The max_allowed_packet variable value is too small or queries require more memory than you have allocated for mysqld. See Section 9, “Packet too large”.

See also See Section 8, “MySQL server has gone away”.

11. The table is full

Common Errors When Using MySQL Programs