Re: logical decoding of two-phase transactions

On 5 January 2017 at 12:43, Stas Kelvich <s(dot)kelvich(at)postgrespro(dot)ru> wrote:
>
>> On 5 Jan 2017, at 13:49, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>>
>> Surely in this case the master server is acting as the Transaction
>> Manager, and it knows the mapping, so we are good?
>>
>> I guess if you are using >2 nodes then you need to use full 2PC on each node.
>>
>> Please explain precisely how you expect to use this, to check that GID
>> is required.
>>
>
> For example if we are using logical replication just for failover/HA and allowing user
> to be transaction manager itself. Then suppose that user prepared tx on server A and server A
> crashed. After that client may want to reconnect to server B and commit/abort that tx.
> But user only have GID that was used during prepare.

I don't think that's the case your trying to support and I don't think
that's a common case that we want to pay the price to put into core in
a non-optional way.

--
Simon Riggs http://www.2ndQuadrant.com/
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