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HomeDatabaseMysql Tutorial如何在oracle中查询数据并同时修改状态

如何在oracle中查询数据并同时修改状态

如何在oracle中查询数据并同时修改状态

这就需要能够查询一批记录并同时修改这批记录的更新状态,以免被正在更新的数据被其他服务器取到

  加行级锁,查询到记录后再遍历结果集更新状态?

  select * from t_musicinfo for update wait 10;

  这样如果某台服务器锁定记录,直到更新状态并提交这段时间,其他所有服务器都得等待,只有这台服务器释放后其他服务器才能加锁进行更新操作,10台服务器同步操作,争抢的机率岂不是很大,有没有办法使查询时对已经锁定的记录视而不见

  Google之...

  果然有:

  select * from t_musicinfo for update nowait skip locked;

  for update skip locked选项是oracle的一个未公开的特性,它的含义是select时跳过被锁的记录

  那么接下来遍历结果集更新状态

  好像不对,结果集打开后再返回,就不能再打开了

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