Large data sets and table partitioning : removing data

Question

Hi,
I have to delete lines into a big table using partition.
Someone says me it is more efficient for the performances to drop a whole partition (or subpartition if I use a composite partition) than to delete a line at the same time.
He says me that data access (in my partition) should be very bad if I delete lines progressively (in this partition) instead of keeping the lines and deleting the whole partition when all its lines are no more used.
What do you think about it?
Thanks
Sandrine

Answer 1

Hi Sandrine,
I agree with what you're being told. I'll be much more efficient to "clone" the data you want to keep from your patition somewhere (clone table, ...) and then drop the whole partition.
Main thing is if you drop an object there's no BEFORE IMAGE stored in your UNDO structures (UNDO TS / RBS). SO you'll have way less disk I/Os.
Hope this helps ^^