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Re: Remote Select opening transaction

From: Marc Demlenne <>
Date: Tue, 3 Apr 2007 14:43:26 +0200
Message-ID: <>


It is ! You can try the following :
- Do a select * from remoteDB.remoteTable_at_remoteHost (but remoteDB is enought, can be same host)
- Don't commit, rollback or quit. Be carefull not to exit in timeout - And monitor the RBS. you'll notice that your sqlplus process is locking one of the RBS, and the number of extent will start growing up and up until you'll recah the ORA-01562 error.
I use :
select, r.curext, t.start_uext, r.extents, t.xidusn, s.sid, s.process, t.start_time
from V$rollstat r, v$rollname rn, V$transaction t, v$session S WHERE t.addr = s.taddr (+) and t.XIDUSN=r.USN AND r.usn(+) = rn.usn

Exiting your sqlplus (or commit or rollback) will unblock the situation, freeing your RBS. In my case, we use the "OPTIMAL" parameter and see the number of extents immediately reducing to it's optimal value ...

Best Regards,

On 4/3/07, Kerber, Andrew W. <> wrote:
> Hi. I am pretty sure your information is incorrect. I have never seen a
> select across a db link open a transaction.
> -----Original Message-----
> *From:* [mailto:
>] *On Behalf Of *Marc Demlenne
> *Sent:* Tuesday, April 03, 2007 7:08 AM
> *To:*
> *Subject:* Remote Select opening transaction
> Hello,
> In Oracle 8, when performing a select query on another database threw DB
> link, Oracle opens a transaction that could only be closed by commit or
> rollback. That could be harmful when developers are not aware of this and
> don't close transaction. (leading to ORA-01562.)
> What is the reason of this behaviour ? Is there some docs / faq explaining
> this ?
> Is this feature also common to later versions of Oracle ?
> Thanks a lot for any piece of information given,
> --
> Marc
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Marc Demlenne

Received on Tue Apr 03 2007 - 07:43:26 CDT

Original text of this message