Concept Question --- Redo Log Recycle

From: jane <janeyiu_at_optonline.net>
Date: Fri, 23 Nov 2001 06:07:41 GMT
Message-ID: <NIlL7.28121$636.5030654@news02.optonline.net>

I'm puzzled about the following scenario. This question is about the inter-workings of online redo log files, DBWn, CKPT...on 8i.
Pls point out anything I said wrong below.

NOARCHIVELOG mode, have a HUGE rollback segment, doing LOTS of modifications, SELECTs, but NO COMMITS.

My question is:
Online redo files will be reused (yes ?), thus CKPT will happen and dirty blocks with UNCOMMITED CHANGES in buffer will be flushed/written to disk (yes ?).

System crashes now.

So what happens after instance is back up ? Since the redo logs have been reused.... How exactly does Oracle roll-forward and undo the UNCOMMITED changes to the disk ?
Read from RBS ?

Pls be as specific as u possibly can.
Really appreciated !

jane Received on Fri Nov 23 2001 - 00:07:41 CST