Oliver Jowett <[EMAIL PROTECTED]> writes:
> Tom Lane wrote:
>> Well, the question is how long must the individual databases retain
>> state with which to answer "recover" requests.

> As I understand it, you don't need to keep state for committed txns, 

I think that's clearly wrong:

        TM --> DB:      COMMIT PREPARED foo

                        DB does it and forgets gid foo

        TM crashes and restarts

        TM --> DB:      what's the state of foo?

        DB --> TM:      go away, never heard of it

I suppose you could code the TM to treat this as meaning "it was
committed" but I think the folly of that is obvious.


> Probably the next question is, do we want a database-side timeout on how 
> long prepared txns can stay alive before being summarily rolled back?

Yeah, there's another set of issues there.  Personally I always thought
that 2PC was a fundamentally broken concept, because it's got so many
squirrelly cases where the guarantees you thought you were buying with
all this overhead vanish into thin air.

                        regards, tom lane

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