You can roll forward to do recovery as long as redo logs are not overwritten 如果重做日志沒有被重新寫入,您就可以通過前滾操作來執(zhí)行恢復(fù)
Db2 list history dropped table all for sample restore table space using the backup image without rolling forward 在沒有前滾操作的情況下,使用備份映像來恢復(fù)表空間。
Both complete and incomplete recovery will be using backup images with or without the roll forward enabled 完全和不完全恢復(fù)都將使用備份映像,可以啟用或不啟用前滾操作
Overflowlogpath - specify the location of the logs during a rollforward operation to allow access logs in multiple locations Overflowlogpath指定前滾操作中的日志位置,以便在多個位置訪問日志。
Reverting is potentially much faster for this purpose than restoring from a backup ; however , you cannot roll forward afterward 采用此方法還原很可能比從備份還原快得多;但是,此后您無法對數(shù)據(jù)進行前滾操作。
As in all point - in - time restore operations , recovering to a mark is disallowed when the database is undergoing operations that are bulk - logged ,前滾操作將在具有指定名稱的第一個標(biāo)記處停止。如果指定了after
Overflowlogpath specify the location of the logs during a rollforward operation to allow access logs in multiple locations Overflowlogpath指定前滾期間可以在哪些目錄搜索需要的日志,以允許前滾操作能訪問多個目錄中的日志。
With five or more cpus , a mirror server distributes its roll forward operations among multiple threads during a failover this is known as parallel redo 如果cpu的數(shù)量為五個或更多時,鏡像服務(wù)器便會在故障轉(zhuǎn)移過程中,在多個線程之間分配其前滾操作(稱為“并行重做
For delta backup and restore , in the same scenario , you will restore each day s delta backup image monday through saturday and roll forward to complete the recovery 對于相同場景中的delta備份和恢復(fù),您將恢復(fù)每天的delta備份映像(星期一到星期六) ,并執(zhí)行前滾操作來完成恢復(fù)。
These failures are handled much the same way in db2 udb and oracle , by restoring either offline or online backups and using roll forward operations to recover the logs 在db2 udb和oracle中,這些失敗的處理方式大致是一樣的,都是通過脫機或聯(lián)機備份并使用前滾操作恢復(fù)日志來完成的。