何时调用mysqli :: close

本文介绍了何时调用mysqli :: close的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我什么时候应该调用mysqli :: close?我从未使用过if语句来检查bind_param()，prep()和execute()是否成功.我应该在method(下面)的末尾调用$ stmt-> close().或者我应该在每个条件之后都调用它以确保关闭数据库连接，即使该过程在某个阶段失败，例如，绑定参数.

When should i call mysqli::close? I never used to use if statements to check whether bind_param(), prep() and execute() were successful. Should I call $stmt->close() at the end of the method(below) . Or should I call it after every condition ensuring that I close the database connection even if the process fails at some stage e.g bind param.

public function function_name($id,$new_id ){ $query = "UPDATE TABLE SET name = ? WHERE field = ? "; if($stmt=$this->prepare($query)){ if($stmt->bind_param("is", $id, $new_id)){ if($stmt->execute()){ }else{//Could not execute the prepared statement $message = "Could not execute the prepared statement"; } }else{//Could not bind the parameters $message = "Could not bind the parameters"; } }else{ $message = "Could not prepare the statement"; } return $message }

推荐答案

PHP退出时，它会正常关闭数据库连接.

When PHP exits it closes the database connections gracefully.

使用close方法的唯一原因是，当您要终止不再使用的数据库连接时，还有很多事情要做:处理和流传输数据，但是如果这样做很快，您可能会忘记结束声明.

The only reason to use the close method is when you want to terminate a database connection that you´ll not use anymore, and you have lots of thing to do: Like processing and streaming the data, but if this is quick, you can forget about the close statement.

将其放在脚本末尾意味着冗余，无性能或内存增加.

Putting it in the end of a script means redundancy, no performance or memory gain.

重要的是:重置未使用的数据，并且如果您想避免内存泄漏(在我的谦虚观点中，这是PHP核心的问题)，请使用:

Whats is important: unset unused data, and if you will want to avoid memory leaks (which in my humble opnion are problem of PHP core in this case) use:

mysqli_kill(); mysqli_close();

这样，套接字也被杀死.

This way the socket is killed too.