php+Mysqli利用事务处理转账问题实例

if($mysqli->connect_errno) {
die('数据库连接失败'.$mysqli->connect_error);
}

$mysqli->autocommit(false); //自动提交模式设为false
$flag = true; //事务是否成功执行的标志

$query = "update account set balance=balance-1000 where id=3";
$result = $mysqli->query($query);
$affected_count = $mysqli->affected_rows;
if(!result || $affected_count == 0) { //失败
$flag = false;
}

$query = "update account set balance=balance+1000 where id=2";
$result = $mysqli->query($query);
$affected_count = $mysqli->affected_rows;
if(!$result || $affected_count == 0) {
$flag = false;
}

if($flag) {
$mysqli->commit();
echo '转账成功';
} else {
$mysqli->rollback();
echo '转账失败';
}

$mysqli->autocommit(true); //重新设置事务为自动提交
$mysqli->close();
?>