Re: [PERFORM] Updates on large tables are extremely slow

[Yves Vindevogel]

I just dropped 19 of the 21 indexes. I just left the primary key constraint and my unique index on 3 fields ...
I did a vacuum full and an analyse .... I just ran the query again some 20 minutes ago.

Guess what .... It's still running !!

So it's not that much faster for the moment.
I just want to update a single field in one table with a simple value (negative value of another field)
That can not be that hard ...

Or is it the MVCC that is responsible for this ?

It can't be indexes on other tables, right ?
That would be absolutely sick

On 13 Jun 2005, at 18:45, Yves Vindevogel wrote:

Ok, if all 21 are affected, I can understand the problem.
But allow me to say that this is a "functional error"

On 13 Jun 2005, at 18:02, Richard Huxton wrote:

Yves Vindevogel wrote:

I forgot cc
Begin forwarded message:

From: Yves Vindevogel <[EMAIL PROTECTED]>
Date: Mon 13 Jun 2005 17:45:19 CEST
To: Tom Lane <[EMAIL PROTECTED]>
Subject: Re: [PERFORM] Updates on large tables are extremely slow

Yes, but if I update one column, why should PG update 21 indexes ?
There's only one index affected !

No - all 21 are affected. MVCC creates a new row on disk.

--
Richard Huxton
Archonet Ltd

Met vriendelijke groeten,
Bien à vous,
Kind regards,

Yves Vindevogel
Implements

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Met vriendelijke groeten,
Bien à vous,
Kind regards,

Yves Vindevogel
Implements

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