Re: Equivalent praxis to CLUSTERED INDEX?

From: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: Adi Alurkar <adi(at)sf(dot)net>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Equivalent praxis to CLUSTERED INDEX?
Date: 2004-08-27 17:48:41
Message-ID: 200408271748.i7RHmfJ15766@candle.pha.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

Adi Alurkar wrote:
> IIRC it it to reduce the "overflow" of data or what oracle calls
> chained rows. i.e if a table has variable length columns and 10 rows
> get inserted into a datapage, if this datapage is full and one of the
> variable length field gets updated the row will now "overflow" into
> another datapage, but if the datapage is created with an appropriate
> amount of free space the updated row will be stored in one single
> datapage.

Agreed. What I am wondering is with our system where every update gets
a new row, how would this help us? I know we try to keep an update on
the same row as the original, but is there any significant performance
benefit to doing that which would offset the compaction advantage?

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Tom Lane 2004-08-27 18:19:29 Re: Equivalent praxis to CLUSTERED INDEX?
Previous Message Adi Alurkar 2004-08-27 17:39:38 Re: Equivalent praxis to CLUSTERED INDEX?