Re: [HACKERS] Maintaining cluster order on insert - Mailing list pgsql-patches

From Gene
Subject Re: [HACKERS] Maintaining cluster order on insert
Date
Msg-id 430d92a20608091831w6e59da84k48a58110cb98e8d6@mail.gmail.com
Whole thread Raw
In response to Re: Maintaining cluster order on insert  ("Jonah H. Harris" <jonah.harris@gmail.com>)
Responses Re: [HACKERS] Maintaining cluster order on insert
List pgsql-patches
I have a table that inserts lots of rows (million+ per day) int8 as primary key, and I cluster by a timestamp which is approximately the timestamp of the insert beforehand and is therefore in increasing order and doesn't change. Most of the rows are updated about 3 times over time roughly within the next 30 minutes. Should I assume that that all of these updates will be on separate pages unless I perform a cluster (which takes a long time) and performance will suffer due to this? Is it possible to preallocate space on the same page for future updates (whatever the average number of updates may be per row) decreasing the number of page loads for querying?

Gene

On 8/9/06, Jonah H. Harris <jonah.harris@gmail.com> wrote:
On 8/9/06, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> UPDATE tries to place the new tuple on the same page it's already
> on.

I think he meant for INSERT.

--
Jonah H. Harris, Software Architect | phone: 732.331.1300
EnterpriseDB Corporation            | fax: 732.331.1301
33 Wood Ave S, 2nd Floor            | jharris@enterprisedb.com
Iselin, New Jersey 08830            | http://www.enterprisedb.com/

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