RE: SQL Oddity

[Vernon Hamberg <vhamberg@xxxxxxxxx>]

Execute STRDBG. Then run your query. If it's in another job, do strsrvjob
first. If a batch job, hold the job queue first, then strsrvjob, then
release the job.

You'll get messages that tell you what index is being used, etc. Also lots
of other info. Would be interesting to know..

At 11:11 AM 3/13/02 -0800, you wrote:
>Eric,
>
>This I would expect from two files.  The only thing was, I had only one file
>I was selecting from.  The exact SQL statement I used was:
>SELECT * FROM INP95 WHERE URID95 = 'PRISM     '
>
>I just can't figure out how SQL got so confused to look at each record 200+
>or so times each to figure out if it was 'PRISM     ' or not.  Perhaps SQL
>was using some weird logical file it had found.  I just don't know.
>
>Regards,
>
>Jim Langston
>
>From: "DeLong, Eric" <EDeLong@Sallybeauty.com>
>
>I've seen this a lot when using sub selects in a statement.  Consider:
>
>Select * from item_master
>where vendor in (select vnd
>                         from vndmst
>                         where crt_date = current_date)
>
>I believe (conjecture based on observation) that if the sub-query returns a
>small result set, say 30 rows, then the SQL optimizer will just scan the
>result set for a match on each item_master record.  For 1 row of
>item_master, if it did not find a match in the sub-query, the number of
>records process would show 31.
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