Subject Re: [firebird-support] Big table and DB slowdowns
Author Jerome Bouvattier
Hi Aage,

----- Original Message -----
From: "Aage Johansen" <aagjohan@...>

[..]
>
> I didn't see an answer, so...

Actually I got help in my follow-up "Optimizer randomly chooses plans (WAS
Big table and DB slowdowns)"
Thanks for joining anyway.

>
> All of these may create problems (bad performance). A high value for 'max
> dup' may make deletes (and updates) very slow.

Yes, I can confirm deletes/updates where damned slow on this table. But the
cause of my trouble is elsewhere. Read my answer to Helen. The slowdowns
occur *randomly* for a SELECT making return in 6 min instead of a few ms.

> Change the indexes to include the primary key, e.g.
> create index PRESENCE_IDX2 on PRESENCE (SALEPRICE,ID);
> This will reduce the 'max dup.' to 1!

I removed the first two already which where left here I don't know why. As
for the third, it's used by an FK. I'm not sure I want to go custom RI in
this particular case.

Thanks for your help.

--
Jerome