可能有不少朋友遇到过这样的问题:
update或delete语句忘带了where子句,或where子句精度不够,执行之后造成了严重的后果,这种情况的数据恢复只能利用事务日志的备份来进行,所以如果你的SQL没有进行相应的全库备份或不能备份日志(truncate log on checkpoint选项为1),那么就无法进行数据的恢复了,或者只能恢复到最近一次的备份的数据了。
以下简单说明恢复数据方法:
1,如果误操作之前存在一个全库备份(或已有多个差异备份或增量备份),首先要做的事就是进进行一次日志备份(如果为了不让日志文件变大而置trunc. log on chkpt.选项为1那你就死翘了)
backup log dbName to disk='fileName'
2,恢复一个全库备份,注意需要使用with norecovery,如果还有其他差异或增量备份,则逐个恢复
restore database dbName from disk='fileName' with norecovery
3,恢复最后一个日志备份即刚做的日志备份,指定恢复时间点到误操作之前的时刻
restore log dbName from disk='fileName'
with stopat='date_time'
以上这些操作都可以在SQL SERVER企业管理器里完成,难度不大。。。
当然,如果误操作是一些不记日志的操作比如truncate table,select into等操作,那么是无法利用上述方法来恢复数据的...

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