Re: One tuple per transaction - Mailing list pgsql-performance

From Tom Lane
Subject Re: One tuple per transaction
Date
Msg-id 2284.1110948270@sss.pgh.pa.us
Whole thread Raw
In response to Re: One tuple per transaction  (Alvaro Herrera <alvherre@dcc.uchile.cl>)
List pgsql-performance
Alvaro Herrera <alvherre@dcc.uchile.cl> writes:
> On Tue, Mar 15, 2005 at 06:51:19PM -0500, Tom Lane wrote:
>> I believe VACUUM already knows that xmin = xmax implies the tuple
>> is dead to everyone.

> Huh, that is too simplistic in a subtransactions' world, isn't it?

Well, it's still correct as a fast-path check.  There are extensions
you could imagine making ... but offhand I agree that it's not worth
the trouble.  Maybe in a few years when everyone and his sister is
using subtransactions constantly, we'll feel a need to optimize these
cases.

            regards, tom lane

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