Re: Performance Question

From: Maxim Demenko <mdemenko_at_arcor.de>
Date: Wed, 26 Apr 2006 16:09:39 +0200
Message-ID: <444f8030$0$4514$9b4e6d93@newsread2.arcor-online.net>

jsfromynr schrieb:
> Hello All,
> In order to find which segment is waiting I ran this statement with
> system user.
> Select EVENT,P1TEXT,P2TEXT,P1,P2,P3 From v$session_wait where
> sid=<sessionid>
> and used the value of P2 as block_id to see which table/index is being
> waited.
> Select segment_name from dba_extents where block_id=<P2>
>
> But I got no rows . Is something I am doing wrong?
>
> With Warm regards
> Jatinder Singh
>

block_id points to the start of extent, you are waiting on block (p2) which may be any between block_id and block_id + blocks - 1 ( from dba_extents ).
Also this query can be pretty expensive...

Best regards

Maxim Received on Wed Apr 26 2006 - 09:09:39 CDT