Oracle数据库操作大全(七)
Oracle中事务处理: 更多Oracle资料、视频教程: http://2.taobao.com/item.htm?id=42922011874spm=686.1000925.0.0.ZVvkz6mt= 注:dml语句(数据操作语言) 事务和锁: 提交事务: 回退事务: 例如:savepoint a1;//设置保存点a1 savepoint a2;//设置保存点
Oracle中事务处理:
更多Oracle资料、视频教程:
http://2.taobao.com/item.htm?id=42922011874&spm=686.1000925.0.0.ZVvkz6&mt=
注:dml语句(数据操作语言)
事务和锁:
提交事务:
回退事务:
例如:savepoint a1;//设置保存点a1
savepoint a2;//设置保存点a2
rollback to a2;//会滚到a2点
rollback;//回滚到最初点,将删除全部保存点
注:运用rollback的前提,不能用commit提交,一旦提交保存点将会被删除
Java程序中如何使用事务:
更多Oracle资料、视频教程:
http://2.taobao.com/item.htm?id=42922011874&spm=686.1000925.0.0.ZVvkz6&mt=
只读事务:
***设置只读:(如机票代售系统,整点统计与购票同时进行)
set transaction read only;(整点统计,只统计整点之前的,不统计当前的)

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