PHP与MYSQL交互函数表学习笔记
最近一直在研究php(做为现在的主流开发语言)与MySQL(和PHP搭配之最佳组合),感觉php(做为现在的主流开发语言)与MySQL(和PHP搭配之最佳组合)交互的函数都是过程化的,当然也有MySQL(和PHP搭配之最佳组合)i扩展,面向对象,Java和C#写多了之后,再写php(做为现在的主流开发语言),有些不适应,感觉又回到了学C的年代。今天学习了一些函数,记录下来,以便日后忘记时,可以参考。
说 明 | 函 数 名 | 函 数 详 细 | 函 数 说 明 |
建立数据库连接 | MySQL(和PHP搭配之最佳组合)_connect() | resource MySQL(和PHP搭配之最佳组合)_connect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]]) 示例:$conn = @MySQL(和PHP搭配之最佳组合)_connect("localhost", "username", "password") or dir("不能连接到MySQL(和PHP搭配之最佳组合) Server"); |
使用该连接必须显示的关闭连接 |
建立数据库连接 | MySQL(和PHP搭配之最佳组合)_pconnect() | resource MySQL(和PHP搭配之最佳组合)_pconnect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]]) 示例:$conn = @MySQL(和PHP搭配之最佳组合)_pconnect("localhost", "username", "password") or dir("不能连接到MySQL(和PHP搭配之最佳组合) Server"); |
使用该连接函数不需要显示的关闭连接,它相当于使用了连接池 |
关闭数据库连接 | MySQL(和PHP搭配之最佳组合)_close() | $conn = @MySQL(和PHP搭配之最佳组合)_connect("localhost", "username", "password") or die("不能连接到MySQL(和PHP搭配之最佳组合) Server"); @MySQL(和PHP搭配之最佳组合)_select_db("MyDatabase") or die("不能选择这个数据库,或数据库不存在"); echo "你已经连接到MyDatabase数据库"; MySQL(和PHP搭配之最佳组合)_close(); |
|
选择数据库 | MySQL(和PHP搭配之最佳组合)_select_db() | boolean MySQL(和PHP搭配之最佳组合)_select_db(string db_name [, resource link_id]) $conn = @MySQL(和PHP搭配之最佳组合)_connect("localhost", "username", "password") or die("不能连接到MySQL(和PHP搭配之最佳组合) Server"); @MySQL(和PHP搭配之最佳组合)_select_db("MyDatabase") or die("不能选择这个数据库,或数据库不存在"); |

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