×
The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.
Walden H. Leverich wrote:
Barbara,
I would imagine though, IF all you cared about was the existence check,
then SETLL would still be the winner since it only involves a trip to
the index, while chain requires a trip to the index, the table-space and
a load of the data. Make sense?
Yes, it does make sense, if the record is more likely to be found than
not found. Although the SETLL also requires a reposition of the file
cursor. But Tim's point in favour of CHAIN makes more sense, for the
current case where the record is 99 times more likely to be not found.
A SETLL would involve a reposition of the file even if the exact record
was not found, unless the search argument was higher than all the
records in the file, while a CHAIN would only require a trip to the index.
I suspect that the relative performance of SETLL and CHAIN is not
determinable, or even guessable, through a thought-experiment. It might
not even be determinable through a performance test, unless the test was
very carefully crafted for a particular file, set of data, and set of
search arguments.
This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact
[javascript protected email address].
Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.
midrange.com
