RE: SQL Oddity

[Jim Langston <jlangston@xxxxxxxxxxx>]

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.