RE: Runtime for deleteing lots of records -- MIDRANGE-L

Subject: RE: Runtime for deleteing lots of records
From: Evan Harris <spanner@xxxxxxxxxx>
Date: Tue, 11 Feb 2003 07:19:36 +1300
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Not to mention the additional disk space you will save by not having to remove the deleted records (or have them hanging around to be reused)

I would bet that not having the deleted records would also improve performance of operations on the file after the purge.

Regards
Evan Harris

Vern wrote:
<SNIP>

The other points, esp. about copying the records you want to keep and clearing the file, are right on, IMO, esp. when the number of deleted records will be most of the file. You can CPYF on a range, and an existing logical will help this, too. You deleted c.72% of the records. Copying the other 28% would mean, at worst, about 40% of the I/O, and could be better, if blocking can be used - deletes are not blocked.

</SNIP?

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