Home Page for the TeradataForum
 

Archives of the TeradataForum

Message Posted: Thu, 05 May 2005 @ 09:55:51 GMT


     
  <Prev Next>  
<<First
<Prev
Next> Last>>  


Subj:   Uniqueness checking on AccLogTbl
 
From:   Anomy Anom

<-- Anonymously Posted: Wednesday, May 04, 2005 20:03 -->

We had a problem with inserts and particularly updates to a table being very slow. We tracked it down to the fact it was defined as a SET table but did not have a unique index - so there was an overhead in enforcing the uniqueness every time an insert or update was done. It was easily fixed once identified.

I wrote a query to list all the SET tables in the system without unique indexes - to see if we might potentially have the same problem elsewhere - most of the tables picked up were too small to be of concern; but one which was not of insignificant size was DBC.AccLogTbl. It has a non-unique primary index of LogonDate, LogonTime.

Should this be of concern? We have logging turned on for all users on nearly all databases for all statements with SQL - and the AccLogTbl was gotten up to about 10Gb.

Do you think the uniqueness checking on this table would be putting any noticeable delay into queries?



     
  <Prev Next>  
<<First
<Prev
Next> Last>>  
 
 
 
 
 
 
 
 
  
  Top Home Privacy Feedback  
 
 
Copyright for the TeradataForum (TDATA-L), Manta BlueSky    
Copyright 2016 - All Rights Reserved    
Last Modified: 27 Dec 2016