Something about PHP

1:   Allowed memory size of 16777216 bytes exhausted

   This is caused by the memory leak, which is set in php.ini, 16M is default size, so you can change it larger the option in php.ini file is :

  step 1 : reset the size

        memory_limit = 16M 

  step 2 : restart the apache

        service apache2 restart 

   (BTW, I am in Unbutu)

 

 

 

2: The difference between mysql and mysqli

 

mysql是非持继连接函数而mysqli是永远连接函数。也就是说

 

mysql每次链接都会打开一个连接的进程而mysqli多次运行mysqli

 

将使用同一连接进程,从而减少了服务器的开销