我想测试InnoDB的行锁怎么测试不了呢?帮忙看下我的代码没错吧?
<code>$u = M('r.goods'); $u->startTrans(); $arr = $u->lock(true)->select(8); ……</code>
注意我没有提交事务哦
现在的问题是:我要怎么来测试锁定呢?
网上说:“要测试锁定的状况,可以利用MySQL 的Command Mode ,开二个视窗来做测试。”
我开了两个命令行窗口A和B,A窗口开启事务,然后sql加锁查询,B窗口不进行任何操作,直接执行同样的加锁查询,感受到了这个“锁定等待”的状态,没有任何问题。
但是为什么我上面写的代码同样的没有提交事务,为什么刷新两次页面没有“锁住,页面卡主”的感觉啊,难道是php脚本执行完后,所开启的事务“自动失效”,还是什么情况呢,还是我写的代码有问题,怎么测试不出来跟命令行窗口中相同的效果呢?
还有一个疑问,我上面B窗口并没有开启事务,只是执行加锁查询,这样也会受影响吗?难道是加锁需要在事务区块中才能生效,而其他的查询时不一定要在事务中是吧,只要是带加锁查询的sql语句才会受上一个事务的影响是吧。
那为何我写的代码测试不出来这个效果呢?
回复内容:
<code>$u = M('r.goods'); $u->startTrans(); $arr = $u->lock(true)->select(8); ……</code>
注意我没有提交事务哦
现在的问题是:我要怎么来测试锁定呢?
网上说:“要测试锁定的状况,可以利用MySQL 的Command Mode ,开二个视窗来做测试。”
我开了两个命令行窗口A和B,A窗口开启事务,然后sql加锁查询,B窗口不进行任何操作,直接执行同样的加锁查询,感受到了这个“锁定等待”的状态,没有任何问题。
但是为什么我上面写的代码同样的没有提交事务,为什么刷新两次页面没有“锁住,页面卡主”的感觉啊,难道是php脚本执行完后,所开启的事务“自动失效”,还是什么情况呢,还是我写的代码有问题,怎么测试不出来跟命令行窗口中相同的效果呢?
还有一个疑问,我上面B窗口并没有开启事务,只是执行加锁查询,这样也会受影响吗?难道是加锁需要在事务区块中才能生效,而其他的查询时不一定要在事务中是吧,只要是带加锁查询的sql语句才会受上一个事务的影响是吧。
那为何我写的代码测试不出来这个效果呢?
大神在哪里,大神在哪里?,帮忙看下啊,为什么我自己打开多个页面测试不出来锁的效果呢?

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