MySQL ÊÂÎñµÄÎÊÌâ

PHP code:

<?php

include("config.inc.php");
$db=new db();
echo date('h:i:s') . "<br />";

$db->execute("begin");

$rs=$db->getRs("select * from book where sum>0 and id =1");
sleep(5);
if($rs->rowCount())//Èç¹û´æÔڿɽèµÄÊé¼®
$db->execute("update book set sum=sum-1 where id =1");

$db->execute("commit");

echo date('h:i:s');

?>



Êý¾Ý¿âΪ
CREATE TABLE `book` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `sum` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk

insert into book(sum) values(1);

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SET autocommit=0;¡¡ºóÔÙÊÔÒ»ÏÂ

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SET autocommit=0;¡¡ºóÔÙÊÔÒ»ÏÂ

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