RE: Just as a learning exercise
Date: Wed, 4 May 2011 09:46:14 -0500
Message-ID: <C970F08BBE1E164AA8063E01502A71CF01AA3040_at_WIN02.hotsos.com>
Roger that. That *IS* where it's useful as a place holder, but nothing more. The good old programming "sub", like writing a PL/SQL procedure with just
BEGIN
NULL;
END;
As the code, it's there and a call to the procedure will always work,
because it does nothing! And it runs really fast too!
But would adding a "NULL" to the top of every PL/SQL block make it run faster? I think we can all agree that it wouldn't, and logically that is about the same thing that adding 1=1 to your query.
Ric Van Dyke
Hotsos Enterprises
Cell 248-705-0624
The 10th Hotsos Symposium
4-8 March 2012 Start making plans now!
-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Michael McMullen
Sent: Wednesday, May 04, 2011 10:34 AM
To: oracle-l_at_freelists.org
Subject: RE: Just as a learning exercise
We use 1=1 a lot for on the fly report generation with different
conditions
that the user can specify, this way "and" statements can just be tacked
on
at the end and then the query run, it's all done via pl/sql.
-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org]
On Behalf Of Ric Van Dyke
Sent: Wednesday, May 04, 2011 10:12 AM
To: Rui.Amaral_at_tdsecurities.com; rjoralist2_at_society.servebeer.com;
oracle-l_at_freelists.org
Subject: RE: Just as a learning exercise
I'm pretty sure that 1=1 has never improved performance of a query; it's
like adding "TURE" to a statement. Certainly since about 9 or so the
optimizer removes it as a predicate, notice the 1=1 predicate isn't
applied
at all in the plan below (yes I truncated the plan so as to fit better):
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