Jim Phillips writes:

>>> Therm-O-Link <[log in to unmask]> 07/02/98
06:33am >>>
Okay, here's a question for all you Image gurus out there:

We have a detail data set that can get fairly full (like 90+%)
before the end of the month.  At the end of the month we move
a lot of the records from this set to another data set that
serves as the history.  We're not talking about a large
amount of records.  Detail_Set_1 has a capacity of 18,425
and 16,657 records, of which 13,223 records will be moved to
Detail_Set_2, so the percent full will go from 90.4% to
18.6%.  Detail_Set_1 has records being constantly added
to it, and then we delete a bunch out during month-end
processing.

My question is this:  What kind of effect (performance-wise)
does this have on data base access?  Will DBPUT's to
Detail_Set_1 take a performance hit because of the long
delete chain?  What about chain pointers and such?  Are
they being affected by this process? Is there anything
I can do with "normal" processing (that is, anything that
does not require exclusive access to the data base/set)
to help things out?

Thanks for all advice/flames/spam.

Jim Phillips                            Manager of Information Systems
E-Mail: [log in to unmask]      Therm-O-Link, Inc.
Phone: (330) 527-2124                   P. O. Box 285
  Fax: (330) 527-2123                   Garrettsville, Ohio  44231
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DBPUTs don't care if they use the delete chain, or the high water mark to
determine record placement.  However, if you don't repack your data set
after your mass delete, any program that serially reads the data set will
continue to read to the high water mark, which could be well past the
last record.

Mike Berkowitz
Guess? Inc.