I'm trying to understand how rollforward works.
my guestion is - Why we need minimum PIT ?
Lets say I have restored db from online backup, and it is now in rollforward pending state - that means db contains some unfinished transactions. So if I have transaction logs - why not to undo all unfinished transactions - the database will be consistent ?
But no we still need to do roll forward at least till minimum PIT.
So if I have transaction logs - why not to undo all unfinished transactions - the database will be consistent ?
Only the logs have info on what the value was before the start of a transaction - specifically, for updates and deletes.
Also, the data in the backup image may be inconsistent, say, T1 in Tbspace1 was backedup at 10.15 with txn was in progress, and T2 in Tbspace2 was backed up at 10.17 when the same txn has been committed. So, how do you rollback ?
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