php+odbc能实现事务进行高并发下单，防止库存不足？怎样把mysql换成odbc
<?php
$conn=mysql_connect("localhost","big","123456");
if(!$conn){
echo "connect failed";
exit;
}
mysql_select_db("big",$conn);
mysql_query("set names utf8");
$price=10;
$user_id=1;
$goods_id=1;
$sku_id=11;
$number=1;
//生成唯一订单号
function build_order_no(){
return date('ymd').substr(implode(NULL, array_map('ord', str_split(substr(uniqid(), 7, 13), 1))), 0, 8);
}
//记录日志
function insertLog($event,$type=0){
global $conn;
$sql="insert into ih_log(event,type)
values('$event','$type')";
mysql_query($sql,$conn);
}
//模拟下单操作
//库存是否大于0
mysql_query("BEGIN"); //开始事务
$sql="select number from ih_store where goods_id='$goods_id' and sku_id='$sku_id' FOR UPDATE";//此时这条记录被锁住,其它事务必须等待此次事务提交后才能执行
$rs=mysql_query($sql,$conn);
$row=mysql_fetch_assoc($rs);
if($row['number']>0){
//生成订单
$order_sn=build_order_no();
$sql="insert into ih_order(order_sn,user_id,goods_id,sku_id,price)
values('$order_sn','$user_id','$goods_id','$sku_id','$price')";
$order_rs=mysql_query($sql,$conn);
//库存减少
$sql="update ih_store set number=number-{$number} where sku_id='$sku_id'";
$store_rs=mysql_query($sql,$conn);
if(mysql_affected_rows()){
insertLog('库存减少成功');
mysql_query("COMMIT");//事务提交即解锁
}else{
insertLog('库存减少失败');
}
}else{
insertLog('库存不够');
mysql_query("ROLLBACK");
}
?>
-- 数据库: big
-- 表的结构 ih_goods
CREATE TABLE IF NOT EXISTS ih_goods (
goods_id int(10) unsigned NOT NULL AUTO_INCREMENT,
cat_id int(11) NOT NULL,
goods_name varchar(255) NOT NULL,
PRIMARY KEY (goods_id)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=2 ;
-- 转存表中的数据 ih_goods
INSERT INTO ih_goods (goods_id, cat_id, goods_name) VALUES
(1, 0, '小米手机');
-- 表的结构 ih_log
CREATE TABLE IF NOT EXISTS ih_log (
id int(11) NOT NULL AUTO_INCREMENT,
event varchar(255) NOT NULL,
type tinyint(4) NOT NULL DEFAULT '0',
addtime timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (id)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
-- 转存表中的数据 ih_log
-- 表的结构 ih_order
CREATE TABLE IF NOT EXISTS ih_order (
id int(11) NOT NULL AUTO_INCREMENT,
order_sn char(32) NOT NULL,
user_id int(11) NOT NULL,
status int(11) NOT NULL DEFAULT '0',
goods_id int(11) NOT NULL DEFAULT '0',
sku_id int(11) NOT NULL DEFAULT '0',
price float NOT NULL,
addtime timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='订单表' AUTO_INCREMENT=1 ;
-- 转存表中的数据 ih_order
-- 表的结构 ih_store
CREATE TABLE IF NOT EXISTS ih_store (
id int(11) NOT NULL AUTO_INCREMENT,
goods_id int(11) NOT NULL,
sku_id int(10) unsigned NOT NULL DEFAULT '0',
number int(10) NOT NULL DEFAULT '0',
freez int(11) NOT NULL DEFAULT '0' COMMENT '虚拟库存',
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='库存' AUTO_INCREMENT=2 ;
-- 转存表中的数据 ih_store
INSERT INTO ih_store (id, goods_id, sku_id, number, freez) VALUES
(1, 1, 11, 500, 0);
