php PDO实现的事务回滚示例

$servername="localhost";
$username="root";
$password="admin";
$dbname="test";
try{
  $conn=new pdo("mysql:host=$servername;dbname=$dbname",$username,$password);
  $conn->setattribute(pdo::attr_errmode,pdo::errmode_exception);
  //开始事务
  $conn->begintransaction();
  $conn->exec("insert into `hello`(`firstname`,`lastname`,`email`)values('ye','xiaming','yexianming@163.com')");
  $conn->exec("insert into `hello`(`firstname`,`lastname`,`email`)values('ye','cong','yecong@163.com')");
  $conn->exec("insert into `hello`(`firstname`,`lastname`,`email`)values('fang','meng','fangmeng@168.com')");
  //提交事务
  $conn->commit();
  echo "new records created successfully!";
}catch(pdoexception $e){
   //回滚事务
   $conn->rollback();
   echo $sql."<br>".$e->getmessage();
}
$conn=null;