Originally posted by quester
Cmon dude, how do you understand both to be true

If one says "A" happens due to "B" and the other says "B" happens due to "A", do you feel they are the same (and looking the process from different angle !?!)... Only one can be a "Catalyst" and the other "Reaction". Both can't be both.

Now coming back to the topic, I guess most want to say that "During Checkpoint, DBWR writes from buffers to files".

See this exact extract from SYBEX Series for OCP DBA 8i - which says - "A checkpoint occurs when the dirty buffers are written to the disk" Now does this mean it's an interpretation mistake of SYBEX.. can we conclude that.. I am looking for some Guru's to acknowledge this..

Regards,
Quester
I think you are getting distracted by semantics. Writing all dirty buffers to disk allows a checkpoint to be taken, and taking a checkpoint requires that all dirty buffers be written to disk. Both of these scenarios make perfect sense, so there oughtn't to be any confusion.

If you come across statements that appear to be contradictory, I suggest that you look at the Oracle documentation to resolve the issue. It took me about 60 seconds to do so myself.