<?php

 try{

 $pdo=new PDO("mysql:host=xxxx;dbname=xxxx","xxxx","xxxx");

 $pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);

 $pdo->setAttribute(PDO::ATTR_AUTOCOMMIT,);

 }catch(PDOException $e){

 echo "数据库连接失败：".$e->getMessage();

 exit;

 }

 //exce()返回影响的行数;

 // $affected_rows=$pdo->exec("insert into shops(name,price,num,desn)values('aa','12.1','10','good')");

 // echo "最后插入的自动增长的id".$pdo->lastInsertId();

 //设置错误报告模式

 //if(!$affected_rows){

 // echo $pdo->errorCode()."<br>";

 // print_r($pdo->errorInfo());

 //}else{

 // echo"执行成功";

 //}

 try{

 $pdo->beginTransaction();

 $price=;

 $sql="update zhanghao set price=price-{$price} where id=1";

 $affected_rows=$pdo->exec($sql);

 $sql="update zhanghao set price=price+{$price} where id=2";

 $affected_rows=$pdo->exec($sql);

 echo("交易成功");

 $pdo->commit();

 }catch(PDOException $e){

 echo $e->getMessage();

 $pdo->rollBack();

 }

 ?>