Skip site navigation (1) Skip section navigation (2)

Bug #474: Index using problem

From: pgsql-bugs(at)postgresql(dot)org
To: pgsql-bugs(at)postgresql(dot)org
Subject: Bug #474: Index using problem
Date: 2001-10-05 07:21:01
Message-ID: 200110050721.f957L1i27238@postgresql.org (view raw or flat)
Thread:
Lists: pgsql-bugs
JoE Olcsak (joe78(at)freemail(dot)hu) reports a bug with a severity of 4
The lower the number the more severe it is.

Short Description
Index using problem

Long Description
I have a problem when using indexes under PostgreSQL 7.1.1 ...

The problem is :
 
  I have a field of table ... This is an INT4 type field ... and I
  created an index for this field like :  
        create index idx_of_field on cim(utod_cim_id);
  ... and I executed a simple query ...

  explain select * from cim where utod_cim_id=0;
  
  NOTICE:  QUERY PLAN:

  Seq Scan on cim  (cost=0.00..6555.41 rows=253633 width=118)

  EXPLAIN
  
  The query optimizer does not use my index..

  I'm executed vacuum analyze command for this table but this not   helps me ... 

  Then I created another index for this field:

  create index idx_of_field2 on cim(int4(utod_cim_id));
  
  ... and I executed another simple query :

   explain select * from cim where int4(utod_cim_id)=0;
   NOTICE:  QUERY PLAN:

   Index Scan using idx_of_field2 on cim  (cost=0.00..6499.70    rows=2536 width=118)

   EXPLAIN
 
What is wrong in the first case ?



Sample Code


No file was uploaded with this report


Responses

pgsql-bugs by date

Next:From: Andreas WernitznigDate: 2001-10-05 09:04:45
Subject: Re: Bug #474: Index using problem
Previous:From: Nathan JohnsonDate: 2001-10-05 01:22:45
Subject: natural join kills postmaster

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group