PHP+MYSQL实现读写分离简单实战

/**

• slave从库返回sql查询结果
• @param $sql
• @return array
  */
  private function slave_select($sql){
  //该处只是随机获取slave节点的ip，当然，还可以采用其他算法获取slave_ip
  $slave_server=$this->get_slave_ip();
  $dsn="mysql:host=$slave_server;dbname=test";
  $user='root';
  $pass='123456';
  $dbh=new PDO($dsn,$user,$pass);
  return $dbh->query($sql)->fetchAll(PDO::FETCH_ASSOC);
  }

/**master主库返回sql执行结果

• @param $sql
• @return int
  */
  private function master_change($sql){
  $master_server='192.168.33.22';
  $dsn="mysql:host=$master_server;dbname=test";
  $user='root';
  $pass='123456';
  $dbh=new PDO($dsn,$pass);
  return $dbh->exec($sql);
  }

/**

• 随机获取slave-ip
• @return mixed
  */
  private function get_slave_ip(){
  $slave_ips=['192.168.33.33','192.168.33.44'];
  $count=count($slave_ips)-1;
  $random_key=mt_rand(0,$count);
  return $slave_ips[$random_key];
  }

/**

• 获取结果
• @return int
  */
  public function get_res(){
  return $this->res;
  }
  }

$sql1 = "select * from t1";
$sql2 = "insert into t1 (name) values ('haha')";
$sql3 = "delete from t1 where id=1";
$sql4 = "update t1 set name='Jerry' where id=2";

$db = new Db($sql1);
//$db = new Db($sql2);
//$db = new Db($sql3);
//$db = new Db($sql4);

var_dump($db->get_res());