Home Page for the TeradataForum
 

Archives of the TeradataForum

Message Posted: Mon, 05 May 2008 @ 20:32:35 GMT


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


Subj:   Re: Regarding the I/O count
 
From:   Michael Larkins

Rahul:

The only way to reduce I/O is to read fewer blocks. There are a couple of potential ways to do this:

1. Index usage

a. Primary columns in WHERE

b. Secondary columns in WHERE

c. NUSI covers (all columns needed) the query

2. larger block size = more rows in block = fewer blocks and the system always does block reads

3. Partitioned Primary Index


Hope this gives you some ideas,


Michael Larkins
Certified Teradata Master
Certified Teradata SQL Instructor



     
  <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