Re: Serious Issue in oracle

From: Andrew Kerber <andrew.kerber_at_gmail.com>
Date: Tue, 26 Jan 2010 07:20:47 -0600
Message-ID: <ad3aa4c91001260520u5ee5bfe5u8428e4a340c6ff0_at_mail.gmail.com>



Uh, guys, he says he is doing a select, not a select for update. He cant be getting a deadlock. He should try comparing the plans when the query runs quickly and the plan when it does not. Are histograms enabled? What is the cursor sharing setting?

On Tue, Jan 26, 2010 at 2:15 AM, Dunbar, Norman < norman.dunbar_at_environment-agency.gov.uk> wrote:

> Morning Thomas,
>
> >> Yep, query gv$session and filter based on username,
> >> schemaname, and sql_id if you know it. Pay close attention
> >> to the event and blocking session columns. That will tell
> >> you if there is some sort of deadlock occurring.
>
> I'm puzzled. I've never seen a deadlock show up in V$SESSION or
> V$SESSION_WAIT before. Any deadlock I've actually seen - I've set up
> myself for testing purposes - usually has one statement killed by Oracle
> and an ORA-60 reported within a second and well before I get a chance to
> check these views.
>
> I know a second is a long time CPU wise, but I'm not all that sure that
> a deadlock will show up in either of these views. I'm interested though
> in knowing whether it does or doesn't - in case anyone has seen them
> show up.
>
> I've got a blog entry on deadlocks at
> http://qdosmsq.dunbar-it.co.uk/blog/?p=192 and I'd like to keep it up to
> date.
>
>
> Cheers,
> Norman.
>
>
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-- 
Andrew W. Kerber

'If at first you dont succeed, dont take up skydiving.'

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Received on Tue Jan 26 2010 - 07:20:47 CST

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