php實作的支援讀寫分離的MySQL類-php教程-PHP中文網

php實作的支援讀寫分離的MySQL類

WBOY

發布： 2016-07-25 08:56:07

原創

936 人瀏覽過

/**
* MySQL讀取與寫入分離類別
* $db_config = array(
* 'master' => array('host'=>'localhost:3306','user'=>'admin',' passwd'=>'123456','db'=>'stat'),
* 'slave' => array(
* array('host'=>'localhost:3307','user'= >'admin','passwd'=>'123456','db'=>'stat'),
* array('host'=>'localhost:3308','user'=>'admin', 'passwd'=>'123456','db'=>'stat')
* )
* );
*
* 註：如果slave有多個時隨機連接其中的一個
* 最後編輯：bbs.it-home.org
*/
/*
$db_config = array(
'master' => array('host'=>'localhost:3306','user'=>'admin','passwd'=>'123456','db'=>' stat'),
'從站' => array(
array('host'=>'localhost:3307','user'=>'admin','passwd'=>'123456 ','db'=>'stat' ),
array('host'=>'localhost:3308','user'=>'admin','passwd'=>'123456', 'db'=>'stat')
)
);
$db = MySQL::getInstance('','r-w');< ;/p>
$sql = "從管理中選擇*";
$rs = $db->query($sql);
while ($row = $db->fetch($rs)){
echo "uid:".$row['uid']." ".$row['userName']."
";
}
echo "

";
*/
class MySQL
{
private static $_instance = null;//資料庫連線實例
private static $_master = null;/ /主資料庫連線實例
private static $_slave = null;//重新資料庫連線實例
public $_config = array();//資料庫連線設定資訊
public $_res = null; //查詢實例句柄
public $_flag = '';//標識目前語句是在主或重資料庫上執行
public $_link = null;
/**
* 單一實例
* 在此輸入描述...
* @paramknown_type $dbname
* @paramunknown_type $mode
* /
public static function & getInstance($dbname='',$mode='rw '){
if (is_null(self::$_instance)){
self::$_instance = new self ();
self::$_instance->__getConf();
self::$_instance->connect($dbname,$mode);
}
return self:: $_instance;
}
/**
* 取得資料庫設定資訊
* Enter description here ...
*/
public function __getConf(){
global $db_config;
$this->_config[🎜> global $db_config;
$this->_config[ 'master'] = $db_config['master'];
$this->_config['slave'] = $db_config['slave'];
}
/**
* 資料庫連線
* Enter description here ...
* @param $dbname 指定連接的資料庫名，預設連接設定檔的函式庫
* @param $mode rw表示連接主庫，r-w表示讀寫分離
*/
public function connect($dbname='' ,$mode = 'rw'){
if($mode == 'rw'){
if(is_null(self::$_master )){
$this->_master = $this ->_slave = $this->conn_master($dbname);
}
}else{
if(is_null(self::$_master )){
$this->_master = $this->conn_master($dbname);
}
if(is_null(self::$_slave)){
$this->_slave = $this->conn_slave($dbname );
}
}
}
/**
* 連接到主資料庫伺服器
* Enter description here ...
*/
public function conn_master($dbname=''){
$_link = mysql_connect( $this->_config['master']['host'],$this->_config['master']['user'],$this->_config['master'] ['passwd'] ,true) 或死亡("連線".$this->_config['master']['host']." 失敗。 ");
mysql_select_db(empty($dbname)?$this->_config ['master']['db']:$dbname,$_link) 或die(" 資料庫名稱".$this->_config[ 'master']['db']." 不存在。") ;
mysql_query("設定名稱utf8",$_link);
return $_link; }
/**
* 連接到從資料庫伺服器
* Enter description here ...
*/
public function conn_slave($dbname=''){
$offset = rand(0,count($this->_config['slave') ])-1);
$_link = @mysql_connect($this->_config['slave'][$offset]['host'],$this->_config['slave'][$offset ][ 'user'],$this->_config['slave'][$offset]['passwd'],true) 或die(" Connect ".$this->_config['slave'][$offset][' host']." 失敗。");
mysql_select_db(empty($dbname)?$this->_config['slave'][$offset]['db']:$dbname,$ _link) 或die( " 資料庫名稱".$this->_config['slave'][$offset]['db']." 不存在。");
mysql_query("設定名稱utf8" ,$_link);
return $_link;
}
/**
* 執行資料庫查詢
* Enter description here ...
* @param string $sql
*/
公用函數查詢($sql,$master=true){
if($master == true || (substr(strtolower($sql),0,6) != 'select') && $master == false){
$this->_res = mysql_query($ sql ,$this->_master);
if(!$this->_res){
$this->_error[] = mysql_error($this->_master);
}
$ this->_flag = 'master';
$this->_link = $this->_master;
} else {
$this->_res = mysql_query($sql ,$this->_slave) ;
if(!$this->_res){
$this->_error[] = mysql_error($this->_slave);
}
$this->_flag = 'slave' ;
$this->_link = $this->_slave;
}
return $this->_res;
}
/**
* 取得單行記錄
* Enter description here ...
* @param mixed $rs
*/
public function get($rs=''){
if(empty($rs) ){
$rs = $this->_res;
}
return mysql_fetch_row($rs);
}
/**
* 取得多行記錄
* Enter description here ...
* @param mixed $rs
* @param $result_type
*/
public function fetch($rs = ''){
if(empty($rs)) {
$rs = $this->_res;
}
return mysql_fetch_array($rs,MYSQL_ASSOC) );
}
/**
* 插入資料
* Enter description here ...
* @param unknown_type $sql
/
* 更新資料
* Enter description here ...
* @param unknown_type $sql
*/
public function add($sql){
$rs = $this->query($sql);
if($rs)
return mysql_insert_id($this->_link);
return false;
}
/**
* 取得上一語句影響的行數
* Enter description here ...
*/
公用函數更新($sql){
if(empty($sql)) return false;
$rs = $this->query($sql);
if($rs)
return $this ->fetchNum();
return false;
}
/**
* 析構函數,釋放資料庫連線資源
* Enter description here ...
*/
public function fetchNum(){
return mysql_affected_rows($this->_link);
}
/***/* 🎜> public function __destruct(){
mysql_close($this->_link);
}
}

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