最近在服务器上面源码编译PHP和Apache以及Nginx组合测试，然而发现了一些问题。一般现在虚拟主机提供都是5.2、5.3较为前沿一些的提供5.4。自己编译当然越新越好，其中又一次编译configure的参数直接复制了一份过来，没有加上–with-mysql只加了–with-mysqli，以前从来感觉不出这两个的区别，编译出来跑一个phpinfo就以为OK了。结果放了一个网站上去打开一看一直是空白页，还以为编译失败了，害我花了一个多小时重新编译一次。然后测试phpinfo正常，才想到去看error_log，才发现是mysql_connect未定义，而且说的是已经废弃。这才发现原来php5.5.x会提示已经废弃的mysql_connect。然而到php官网找到如下文档。

ext/mysqli PDO_MySQL ext/mysql

PHP version introduced 5.0 5.1 2.0

Included with PHP 5.x Yes Yes Yes

Development status Active Active Maintenance only

Lifecycle Active Active Deprecated

Recommended for new projects Yes Yes No

OOP Interface Yes Yes No

Procedural Interface Yes No Yes

API supports non-blocking, asynchronous queries with mysqlnd Yes No No

Persistent Connections Yes Yes Yes

API supports Charsets Yes Yes Yes

API supports server-side Prepared Statements Yes Yes No

API supports client-side Prepared Statements No Yes No

API supports Stored Procedures Yes Yes No

API supports Multiple Statements Yes Most No

API supports Transactions Yes Yes No

Transactions can be controlled with SQL Yes Yes Yes

Supports all MySQL 5.1+ functionality Yes Most No