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@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Michael McMullen Sent: Wednesday, May 04, 2011 10:34 AM To: oracle-l@xxxxxxxxxxxxx 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@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Ric Van Dyke Sent: Wednesday, May 04, 2011 10:12 AM To: Rui.Amaral@xxxxxxxxxxxxxxxx; rjoralist2@xxxxxxxxxxxxxxxxxxxxx; oracle-l@xxxxxxxxxxxxx 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): -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l