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Message Posted: Fri, 14 Mar 2003 @ 11:09:36 GMT
Subj: | | Re: Deleting from a huge table |
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From: | | Anantaraman, Kumaran (K.) |
I ran a test and I found unexpected results favoring mload delete over insert-select.
wall time in secs (mload = 75, insert-select = 2160)
AMP CPU (mload = 1686, insert-select = 39067)
Disk I/O (mload = 4305018, insert-select = 14124056)
The table had 500 mill rows and I was deleting 100 mill (20%) on a WHERE on a non-PI column date column. There are no SIs, and there
were no blocking during the runs. I am using V2R4.1
What could explain the above results?
Kumaran Anantaraman
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