How to connect to the database in singleton mode

This article mainly introduces the method of connecting to the database in singleton mode. It has certain reference value. Now I share it with you. Friends in need can refer to it

<?php

class Db {
    static private $_instance;
    static private $_connectSource;
    private $_dbConfig = array(
        &#39;host&#39; => &#39;127.0.0.1&#39;,
        &#39;user&#39; => &#39;root&#39;,
        &#39;password&#39; => &#39;&#39;,
        &#39;database&#39; => &#39;video&#39;,
    );

    private function __construct() {
    }

    static public function getInstance() {
        if(!(self::$_instance instanceof self)) {
            self::$_instance = new self();
        }
        return self::$_instance;
    }

    public function connect() {
        if(!self::$_connectSource) {
            self::$_connectSource = @mysql_connect($this->_dbConfig[&#39;host&#39;], $this->_dbConfig[&#39;user&#39;], $this->_dbConfig[&#39;password&#39;]);    

            if(!self::$_connectSource) {
                throw new Exception(&#39;mysql connect error &#39; . mysql_error());
                //die(&#39;mysql connect error&#39; . mysql_error());
            }
            
            mysql_select_db($this->_dbConfig[&#39;database&#39;], self::$_connectSource);
            mysql_query("set names UTF8", self::$_connectSource);
        }
        return self::$_connectSource;
    }
}
/*$connect = Db::getInstance()->connect();

$sql = "select * from video";
$result = mysql_query($sql, $connect);
echo mysql_num_rows($result);
var_dump($result);*/

The above is the entire content of this article. I hope it will be helpful to everyone's study. For more related content, please pay attention to the PHP Chinese website!

Related recommendations:

How to use fastcgi_finish_request to improve page response speed

The above is the detailed content of How to connect to the database in singleton mode. For more information, please follow other related articles on the PHP Chinese website!