Re: Useful SQL tip for handling optional parameters

I should specify that if all you have is

where :value2 in ('*ALL',FIELD2)

then it will do a table scan when value2 is '*ALL', however, should use an
access path when not. Like I said that's been my experience. It's been
awhile and could be wrong.

On Wed, Dec 7, 2016 at 4:53 PM, Michael Schutte <mschutte369@xxxxxxxxx>
wrote:

An alternative format I've seen that's useful
where FIELD1 = :parm1 and
:value2 in ('*ALL', FIELD2);

Won't that require a table scan vs. what he had originally?

My experience with it is that the query will look for another access path.
when value2 is *ALL. Likely one with FIELD1. If value2 isn't *ALL,
attempts to find an access path with both field1 and field2.

I've never seen it to a table scan because of it. It's really just a
fancy OR.


On Wed, Dec 7, 2016 at 12:12 PM, <dlclark@xxxxxxxxxxxxxxxx> wrote:

"RPG400-L" <rpg400-l-bounces@xxxxxxxxxxxx> wrote on 12/07/2016 12:07:23
PM:

An alternative format I've seen that's useful
where FIELD1 = :parm1 and
:value2 in ('*ALL', FIELD2);

Won't that require a table scan vs. what he had originally?


Sincerely,

Dave Clark
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