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Message Posted: Fri, 19 Apr 2002 @ 08:34:40 GMT
Subj: | | Re: NULLs and Comparisons |
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From: | | Anomy Anom |
<-- Anonymously Posted: Thursday, April 18, 2002 23:10 -->
Hi:
The update is not occurring because your WHERE clause is returning a false.
The result, step by step:
Step 1
WHERE X = :IN_x <--- TRUE
> AND (Y <> :IN_y OR <---- FALSE
> Z <> :IN_Z) <--- Unknown
Step 2
WHERE TRUE AND Unknown <--- FALSE
with an AND condition, both sides of the AND must be TRUE and here, they are not. So, the update does not take place.
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