Re: Problematic Index Scan - Mailing list pgsql-general

From Richard Huxton
Subject Re: Problematic Index Scan
Date
Msg-id 200207291534.08243.dev@archonet.com
Whole thread Raw
In response to Problematic Index Scan  (Tourtounis Sotiris <tourtoun@csd.uoc.gr>)
List pgsql-general
On Monday 29 Jul 2002 1:35 pm, Tourtounis Sotiris wrote:
> Anyone for help !!!!
> I have a table with 3 attributes(int8, int8, int respectively) and I load
> to it a batch file of 150000 tuples,
> I make some SQL questions on them
> in order to use the created b-trees on the first attribute and for 3-4
> times there is an index scan on it as it used to be. However, after those
> 3-4 times the database start to use sequential scan on this first index.

Can't say I've ever seen this.

> The only way is to make
> index scan  work is to drop the whole database where the table is in and
> re-installed it from the beggining. I wonder if there is an explanation of
> that phenomenon and how i can assure the index scan function without the
> reinstallation of the whole table.

Never seen this. What people are going to need if they are to help you is the
EXPLAIN output both before and after this problem occurs. I'm assuming you
are running VACUUM ANALYSE after loading the data.

- Richard Huxton

pgsql-general by date:

Previous
From: Tom Lane
Date:
Subject: Re: Is there any such thing as PostgreSQL security on a hosted website?
Next
From: Tom Lane
Date:
Subject: Re: tsearch - Regression tests fail