Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.server -> Re: UNION: SQL-tuning

Re: UNION: SQL-tuning

From: Billy Verreynne <vslabs_at_onwe.co.za>
Date: Thu, 12 Sep 2002 09:57:59 +0200
Message-ID: <alphfa$bp8$1@ctb-nnrp2.saix.net> 






Jan Gelbrich wrote:



> - did You use UNION ALL ?  It is said to be better than a mere UNION.




Not better. Different.



UNION - this eliminates duplicates (i.e. performs a select distict in 
effect).



UNION ALL - does not eliminate duplicates.



Make sure you are using the right SQL for the job.


--
Billy


Received on Thu Sep 12 2002 - 02:57:59 CDT












Original text of this message













  HOME |
  ASK QUESTION |
  ADD INFO |
  SEARCH |
  E-MAIL US