Return-Path: Delivered-To: 2-oracle-l@orafaq.com Received: (qmail 12734 invoked from network); 20 Dec 2007 13:02:41 -0600 Received: from freelists-180.iquest.net (HELO turing.freelists.org) (206.53.239.180) by static-ip-69-64-49-119.inaddr.intergenia.de with SMTP; 20 Dec 2007 13:02:40 -0600 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id B527A7DD8BE; Thu, 20 Dec 2007 14:02:41 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing.freelists.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 11922-09; Thu, 20 Dec 2007 14:02:41 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 2EADD7DD7CE; Thu, 20 Dec 2007 14:02:41 -0500 (EST) Received: with ECARTIS (v1.0.0; list oracle-l); Thu, 20 Dec 2007 13:15:16 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 427467DDA8D for ; Thu, 20 Dec 2007 13:15:16 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing.freelists.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 06199-06 for ; Thu, 20 Dec 2007 13:15:16 -0500 (EST) Received: from wr-out-0506.google.com (wr-out-0506.google.com [64.233.184.235]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id F22177DDA46 for ; Thu, 20 Dec 2007 13:15:15 -0500 (EST) Received: by wr-out-0506.google.com with SMTP id c49so2460537wra.1 for ; Thu, 20 Dec 2007 10:15:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:references; bh=zs47bw+m81lkMP8e5Co37aIH6f5RkaZto5E/4kDvi3E=; b=uXjq41bKEgDvslak3sm1ObEx3DurNPO4+L0uyUE80Zmgka95W++ObIbnG717XHoKUFKtYo2jznlHaHltgnW9aFPOQfFHSLb1r6kpgxQQ4OqhDBo3hpPkgA2R04JDCKrb62aIhLEF5rSIsX3kvtGhn9VXKcaRrjbvHz7DUaa5SHg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:references; b=AoNgToZkdP3uhKnusyuWbeZ3KTbPKJ4RByIcr3bxQVHiNPKuBAlebZ0vJoz+yEmZrvUPKyQ0Ge7XCbeI/x1cgeXJHq/da3uvrSgJUbKw+JgQhVfPUemyy3JlEqvYbQPRWXsHfNYkfEft4R8HQPLi9zUJOxwiPxBCmXjnTZBUWDA= Received: by 10.143.6.1 with SMTP id j1mr237979wfi.45.1198174513932; Thu, 20 Dec 2007 10:15:13 -0800 (PST) Received: by 10.142.11.19 with HTTP; Thu, 20 Dec 2007 10:15:13 -0800 (PST) Message-ID: Date: Thu, 20 Dec 2007 10:15:13 -0800 From: "Jared Still" To: genegurevich@discover.com Subject: Re: Do selects block truncates? Cc: oracle-l In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_28956_24718862.1198174513961" References: <607D6181D9919041BE792D70EF2AEC482434DC@LIMENS.sivsa.int> X-archive-position: 4048 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-to: oracle-l-bounce@freelists.org X-original-sender: jkstill@gmail.com Precedence: normal Reply-to: jkstill@gmail.com List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: oracle-l X-List-ID: oracle-l List-subscribe: List-owner: List-post: List-archive: X-list: oracle-l X-Virus-Scanned: Debian amavisd-new at localhost.localdomain ------=_Part_28956_24718862.1198174513961 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline On Dec 20, 2007 9:43 AM, wrote: > > I am running oracle 10.2.0.2 and I see two sessions running truncate > commands being stuck. It looks like they are > waiting on another session which is currently running a long select. That > select accesses both of the tables that > the other two sessions are trying to truncate. I was not aware that a > select can block a truncate. Is that the case > or is there something else here which I am missing? > I don't believe that the SELECT is blocking the truncate. This is easy to test. In session 1: drop table rbg; create table rbg as select * from dba_objects / insert /*+ append */ into rbg select * from rbg; commit; insert /*+ append */ into rbg select * from rbg; commit; insert /*+ append */ into rbg select * from rbg; commit; insert /*+ append */ into rbg select * from rbg; commit; In session 2: select * from rbg; Back to session 1: truncate table rbg; Back to session 2: PUBLIC /588bb8e2_ObjectStreamField 30790 SYNONYM 08/14/2006 14:37:42 04/13/2007 17:59:12 2006-08-14:14:37:42 VALID N N N ERROR: ORA-08103: object no longer exists 22700 rows selected. This is on 10.2.0.3 -- Jared Still Certifiable Oracle DBA and Part Time Perl Evangelist ------=_Part_28956_24718862.1198174513961 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline On Dec 20, 2007 9:43 AM, <genegurevich@discover.com> wrote:

I am running oracle 10.2.0.2 and I see two sessions running truncate
commands being stuck. It looks like they are
waiting on another session which is currently running a long select. That
select accesses both of the tables that
the other two sessions are trying to truncate. I was not aware that a
select can block a truncate. Is that the case
or is there something else here which I am missing?

I don't believe that the SELECT is blocking the truncate.

This is easy to test.

In session 1:

drop table rbg;

create table rbg
as
select *
from
dba_objects
/

insert /*+ append */
into rbg
select * from rbg;

commit;

insert /*+ append */
into rbg
select * from rbg;

commit;

insert /*+ append */
into rbg
select * from rbg;

commit;

insert /*+ append */
into rbg
select * from rbg;

commit;

In session 2:

select * from rbg;

Back to session 1:
truncate table rbg;

Back to session 2:

PUBLIC     /588bb8e2_ObjectStreamField                                        30790
SYNONYM             08/14/2006 14:37:42 04/13/2007 17:59:12 2006-08-14:14:37:42 VALID   N N N

ERROR:
ORA-08103: object no longer exists

22700 rows selected.

This is on 10.2.0.3


--
Jared Still
Certifiable Oracle DBA and Part Time Perl Evangelist
------=_Part_28956_24718862.1198174513961-- -- http://www.freelists.org/webpage/oracle-l