Show us the relent dictionary items, the SQL statement, and the "LIST.INDEX 
{filename} ALL" output

You should also try native SELECT commands using the index to see if 
performance is as expected.
SELECT ... FROM CUSTOMER WHERE I_ZIP = "12345";                 vs

Also, try including "REQUIRE.INDEX" and then "NO.INDEX" at the back end of your 
command to see the difference.
The 'REQUIRE.INDEX' will fail if the selected index could not be used:

           Use in a  RetrieVe  command  to  specify  that  secondary  key
           indexes  must  be  used  to  process  the sentence. If indexes
           cannot be used, an error message appears and the sentence does
           not proceed.

The 'NO.INDEX' will bypass the use of an index, showing the resulting 
performance change:

           Use in a  RetrieVe  command  to  specify  that  secondary  key
           indexes not be used if they exist. This is useful when indexes
           are not up to date or built.

Finally, the order of occurrence of the selection criteria can impact the use 
of secondary indices.

... david ...

David L. Wasylenko
President, Pick Professionals, Inc
w) 314 558 1482

-----Original Message-----
[] On Behalf Of Allen Egerton
Sent: Friday, July 27, 2012 10:35 AM
To: .U2 List
Subject: [U2] Universe; SQL; Indexes?? (10.3.7 on Windows)

I'm using SQL to query Universe 10.3.7 data files, (ANSi-compliant and 
non-compliant formats) and indexing the files to try to optimize the 
performance seems in some cases to have little or no effect.

I'm pretty clear on index behavior with Universe's native query language, but 
SQL is somewhat unfamiliar to me, and I'm wondering why I'm not getting the 
behavior I expect.

Can anyone either point me to reference material on this, or offer thoughts 
based on experience?

Thank you.

Allen Egerton;
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