Re: Transaction Exception Question - Mailing list pgsql-general

From Andrew Sullivan
Subject Re: Transaction Exception Question
Date
Msg-id 20020814174831.H15973@mail.libertyrms.com
Whole thread Raw
In response to Re: Transaction Exception Question  (Jon Swinth <jswinth@atomicpc.com>)
List pgsql-general
On Wed, Aug 14, 2002 at 01:56:57PM -0700, Jon Swinth wrote:
> ah, now I understand where you got FK from.  The transaction exeception I run
> into most often is caused by an Unique Key (not the PK either).  An insert
> will block on UK violation when the existing record has been inserted from a
> non-complete transaction.

Ok, so these are just separate issues.  Sorry, I'm especially dim
this week (we're moving offices is my best excuse).

> As for your pending and posted idea, are you proposing to not have FK on the
> pending table?  What do I do when the order fails an FK when moving from
> pending to posted?  The whole point of the transaction is that when I am
> done, everything is updated properly or nothing is updated.

No, you should have the FKs on the pending table.  Hmm.  I see, now:
the problem may be related also to the long-running transaction,
because you end up having to take the lock for the duration.  So
never mind all of what I said.

> Based on what I know of Postgre so far, there are two ways to solve the FK
> lock issues.  Both require that the concept of read lock be added to the core
> of postgre.

Yes, I think this is right.  And yes, that lock mechanism would be
valuable.

A

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