Re: Store FullTransactionId in TwoPhaseFileHeader/GlobalTransactionData

On Thu, Aug 1, 2019 at 5:36 PM Thomas Munro <thomas(dot)munro(at)gmail(dot)com> wrote:
>
> Hi Vignesh,
>
> On Thu, Aug 1, 2019 at 9:32 PM vignesh C <vignesh21(at)gmail(dot)com> wrote:
> > In the undo system, we use full-transaction-id for transactions. For
> > rollback of prepared transactions, we were planning to use
> > FullTransactionId by combining TransactionId and epoch, but as
> > suggested by multiple people in that email chain [1][2], the better
> > idea is to store Full-transactionid in TwoPhaseFileHeader
>
> +1
>
> > Backward compatibility need not be handled for this scnario as upgrade
> > does not support having open prepared transactions.
>
> +1
>
> > There is also one more comment which is yet to be concluded. The
> > comment discusses about changing subxids which are of TransactionId
> > type to FullTransactionId type being written in two phase transaction
> > file. We could not conclude this as the data is similarly stored in
> > TransactionStateData.
>
> No comment on that question or the patch yet but could you please add
> this to the next Commitfest so that cfbot starts testing it?
>
I have added it to the commitfest.

Regards,
Vignesh
EnterpriseDB: http://www.enterprisedb.com