Re: Gsoc2012 Idea --- Social Network database schema - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Gsoc2012 Idea --- Social Network database schema
Date
Msg-id 2016.1332345640@sss.pgh.pa.us
Whole thread Raw
In response to Re: Gsoc2012 Idea --- Social Network database schema  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> Well, there's something mighty tempting about having a way to say
> "just give me a random sample of the blocks and I'll worry about
> whether that represents a random sample of the rows".

> It's occurred to me a few times that it's pretty unfortunate you can't
> do that with a TID condition.

> rhaas=# explain select * from randomtext where ctid >= '(500,1)' and
> ctid < '(501,1)';

Yeah, as you say that's come up more than once in data-recovery
situations.  It seems like it'd be just a SMOP to extend the tidscan
stuff to handle ranges.

Another thing that people sometimes wish for is joins using TIDs.
I think the latter would actually be pretty trivial to do now given the
parameterized-plan infrastructure; I'd hoped to look into it for 9.2 but
ran out of time...
        regards, tom lane


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