What do you mean: Index cannot be used directly in the program?
1. an SQL Index can be used in composition with native I/O like any DDS
described logical file)
2. Specifying a logical file in an SQL SELECT statement was never a good
idea. The query optimizer has to rewrite the SELECT statement based on the
underlying physical files or SQL Tables based on the Field-Selection, Join
and SELECT/OMIT clauses in the LF description. Key information is not
considered when rewriting the SELECT-Statement ... after the optimization
starts. (If the same logical file as specified is used it is not more than
by hazard).
... also SQL Indexes are much more powerful (even in composition with native
I/O) than DDS described logical file, i.e. Derived Keys (additional key
fields based on SQL Functions or mathematic operations) and Sparse Indexes
(with WHERE conditions much more powerful than SELECT omit clauses)
Mit freundlichen Grüßen / Best regards
Birgitta Hauser
Modernization ? Education ? Consulting on IBM i
IBM Champion since 2020
"Shoot for the moon, even if you miss, you'll land among the stars." (Les
Brown)
"If you think education is expensive, try ignorance." (Derek Bok)
"What is worse than training your staff and losing them? Not training them
and keeping them!"
"Train people well enough so they can leave, treat them well enough so they
don't want to. " (Richard Branson)
"Learning is experience ? everything else is only information!" (Albert
Einstein)
-----Original Message-----
From: MIDRANGE-L <midrange-l-bounces@xxxxxxxxxxxxxxxxxx> On Behalf Of
Timothy Feldmeier
Sent: Tuesday, 16 May 2023 14:27
To: MIDRANGE-L@xxxxxxxxxxxxxxxxxx
Subject: Can SQL DDL views have the same capability as a DDS Logical view?
I want to stop creating DDS logical views-but, I want the DDL view to have
the same capability as the logical view. I don't want to create an Index,
that can't directly be used in the program.
Thank You
Tim Feldmeier
Programmer Analyst, Applications Development
1431 Opus Place, Suite 530 | Downers Grove, IL 60515
Email: timothy.feldmeier@xxxxxxxx<mailto:timothy.feldmeier@xxxxxxxx>
Phone: (331) 233-7921
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