Why use it : SELECT 1 FROM DUAL

From: Eriovaldo Andrietta <ecandrietta@xxxxxxxxx>
To: ORACLE-L <oracle-l@xxxxxxxxxxxxx>
Date: Thu, 2 Aug 2012 14:52:39 -0300

Hello friends,
I am analyzing some sql statments and found out in all queries the
developer added the following where clause plus others...

   and exists (select 1 from dual)


All queries has this code.

Is there any good reason to put it in the sql statment ?
Does it improve performance ?

This is the first time I see it in SQL ?

Regards
Eriovaldo


--
//www.freelists.org/webpage/oracle-l

Follow-Ups:
- Re: Why use it : SELECT 1 FROM DUAL
  - From: Robert Hanuschke
- Re: Why use it : SELECT 1 FROM DUAL
  - From: Tim Gorman

Other related posts:

» Why use it : SELECT 1 FROM DUAL - Eriovaldo Andrietta
» Re: Why use it : SELECT 1 FROM DUAL- Robert Hanuschke
» Re: Why use it : SELECT 1 FROM DUAL- Tim Gorman
» Re: Why use it : SELECT 1 FROM DUAL- Eriovaldo Andrietta
» Re: Why use it : SELECT 1 FROM DUAL- Rodd Holman