PHP访问数据库的问题标题要长。
一直纠结几个问题
第一、就是浏览器给服务器一个请求，服务器端就会创建一个新的线程来处理相应的请求然后返回给浏览器吗？
第二、
如果访问的是如下代码
<?php$con = mysql_connect("localhost","peter","abc123");if (!$con) die('Could not connect: ' . mysql_error()); $strsql="SELECT * FROM `gbook`"; // 执行sql查询$result=mysql_db_query("database", $strsql, $con);// 获取查询结果 $row=mysql_fetch_row($result);?>那么服务器端就会创建一个新线程来执行这段代码，进行数据库链接和查询
那么如果有N个用户在一分钟内访问，那么就会在这一分钟内创建N个线程，链接N次数据库吗？
在window下，mysql_connect这个函数应该调用的是.dll动态链接库不，这样的话每个用户访问一次都要重新链接一次数据库，这样效率高吗？还是这几个线程共享一次数据库链接。。。
本人小白，大神勿喷啊，，
回复讨论(解决方案)
没人回答吗。。。额额额。。。额额额。。。额
是新进程...
用户访问网页， mysql就会创建一次连接。
1、每个 http 会话占用一个独立的进（线）程，这样才能保证会话的独立性
2、请注意加载和连接的区别，动态链接库是只加载一次的，每个使用它的程序都对他产生一个连接
3、如果你设想若干进（线）程共享一个连接，并不是不可做到的。只是各进（线）程间的调度会异常复杂。你打算怎样标识数据流来保证不会张冠李戴呢？
那如果一万个人在很短时间内都访问服务器那就要创建一万个进（线）程？而且每个进（线）程的生命周期就只有用户访问，服务器返回这很短的时间吗？
每个进（线）程都独立的拥有一个与数据库的链接吗？
比如$con = mysql_connect("localhost","peter","abc123");这个链接函数，建立一次本地的数据库链接，时间会很长吗？
传统web服务器确实是一个请求一个线程，处理完就释放掉
本身HTTP协议设计的目的就是解决web这种轻量高并发的需求
nginx貌似不是开线程，有性能更高的解决方案，有兴趣百度下吧
数据库连接也是线程独立的
但现在很多地方都在使用“池”，比如内存池，线程池
意思是在服务器和数据库之间多加一层服务，它预先和数据库申请好N个连接，保存句柄并保持住，前面有服务器要访问数据库的时候，直接使用已经连接好的句柄，用完放回去但不释放
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