mysqli::close

mysqli_close

(PHP 5)

mysqli::close -- mysqli_close — Closes a previously opened database connection

说明

面向对象风格

bool mysqli::close ( void )

过程化风格

bool mysqli_close ( mysqli $link )

Closes a previously opened database connection.

参数

link: 仅以过程化样式：由 mysqli_connect() 或 mysqli_init() 返回的链接标识。

返回值

成功时返回 TRUE，或者在失败时返回 FALSE.

范例

See mysqli_connect().

参见

mysqli_connect() - 别名 mysqli::__construct
mysqli_init() - Initializes MySQLi and returns a resource for use with mysqli_real_connect()
mysqli_real_connect() - Opens a connection to a mysql server

PHP手册 - N: Closes a previously opened database connection

用户评论:

Anonymous (23-Apr-2010 10:43)

The mysqli_close() function and object method only remove the ability to use the mysql object again in the script, essentially on the surface only nulling out all object parameters. At least with PHP5.3.2 and Windows connecting by tcp, this differs by the old mysql_close() function in that it does not actually close out the tcp socket being used. You should always use mysqli_kill() function before mysqli_close() to actually close and free up the tcp socket being used by PHP. Garbage collection after script execution nor mysqli_close() do not kill the tcp socket on their own. The socket would otherwise remain in 'wait' state for approximately 30 seconds, and any additional page loads/connection attempts would only add to the total number of open tcp connections. This wait time does not appear to be configurable via PHP settings. Also as of this version, mysqli created links cannot be "deactivated", and will continue to accumulate in process memory until the PHP server or process is restarted, essentially making mysqli.max_links = -1 required.

php at dafydd dot com (07-Nov-2008 09:03)

I've had situations where database connections appeared to persist following php execution. So, now, my __destructor function explicitly contains a $cxn->close(). It hurts nothing, and helps avoid memory leaks.

win at alinto dot com (21-May-2008 10:52)

There's nothing here about connexions automatically claused at the end of a script. About that, a little note from devzone.zend.com : "Open connections (and similar resources) are automatically destroyed at the end of script execution. However, you should still close or free all connections, result sets and statement handles as soon as they are no longer required. This will help return resources to PHP and MySQL faster."