PHP防止多个MySQL连接

Question

I have a large procedural style php/mysql website, which is splitted into many different files. Within each file, i include my dbconn.php, to ensure, that a db connection is available.

It looks something likes this:

index.php

<?php 
   include_once ('header.php');
   include_once ('nav.php');
   include_once ('content.php');
   include_once ('sidebar.php');
   include_once ('footer.php');
?>

and within each of these files i call several other files via include_once. So in total i come up with about 30 different files.

Every file starts with:

include_once($_SERVER['DOCUMENT_ROOT'].'/dbconn.php');

Since i'm using include_once, dbconn.php should not be loaded more then once, but recently i get following php warning.

PHP Warning:  mysqli_connect(): (HY000/1226): User 'username' has exceeded the 'max_user_connections' resource (current value: 20) in /var/www/html/dbconn.php on line 10

My dbconn.php looks like this:

<?php
   $host = "localhost";
   $user = "username";
   $pass = "password";
   $db = "dbname";

   if(!mysqli_thread_id($con)){
       $con = mysqli_connect($host, $user, $pass, $db);
       mysqli_set_charset($con, 'utf8');
   }
   unset($host,$user,$pass,$db);
?>

So there is a double check. If there already is an open mysql connection, the file should do basicly nothing.

What am i doing wrong? Why do i get this php warning and how do i reduce the amount of mysql connections?

Answer 1

Basically, it's not different calls from a single page that is leading to the problem. It's the fact that you have multiple OPEN connections at the moment.

Make sure you close you connections after they have served their purpose.

Also, try to avoid the kind of structure you currently have, have all the DB related stuff included in one file and then include it only once on your page.