Re: Transactions involving multiple postgres foreign servers

On Fri, Oct 21, 2016 at 1:38 AM, Ashutosh Bapat
<ashutosh.bapat@enterprisedb.com> wrote:
> Once we have that information, the foreign server can actively poll
> the local server to get the status of transaction xid and resolves the
> prepared transaction itself. It can go a step further and inform the
> local server that it has resolved the transaction, so that the local
> server can purge it from it's own state. It can remember the fate of
> xid, which can be consulted by another foreign server if the local
> server is down. If another transaction on the foreign server stumbles
> on a transaction prepared (but not resolved) by the local server,
> foreign server has two options - 1. consult the local server and
> resolve 2. if the first options fails to get the status of xid or that
> if that option is not workable, throw an error e.g. indoubt
> transaction. There is probably more network traffic happening here.
> Usually, the local server should be able to resolve the transaction
> before any other transaction stumbles upon it. The overhead is
> incurred only when necessary.

Yes, something like this could be done.  It's pretty complicated, though.

-- 
Robert Haas
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