Re: add column with default value is very slow - Mailing list pgsql-performance

From hubert depesz lubaczewski
Subject Re: add column with default value is very slow
Date
Msg-id 20120911140554.GA8922@depesz.com
Whole thread Raw
In response to Re: add column with default value is very slow  (AI Rumman <rummandba@gmail.com>)
List pgsql-performance
On Tue, Sep 11, 2012 at 08:04:06PM +0600, AI Rumman wrote:
> Table size is 1186 MB.

if it takes long, it just means that your IO is slow.

> I split the command in three steps as you said, but the result same during
> the update operation.

three? I was showing four steps, and one of them is usually consisting
hundreds, if not thousands, of queries.

> One more thing, I have just restored the db from dump and analyzed it and
> I am using Postgresql 9.1 with 3 GB Ram with dual core machine.

so it looks like your IO channel is slow.

Best regards,

depesz

--
The best thing about modern society is how easy it is to avoid contact with it.
                                                             http://depesz.com/


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