Message-ID: <548620B3.4030205@BlueTreble.com>
Date: Mon, 8 Dec 2014 16:05:39 -0600
From: Jim Nasby <Jim.Nasby@BlueTreble.com>
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To: Robert Haas <robertmhaas@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>
CC: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Andres Freund
 <andres@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Bruce
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Subject: Re: On partitioning
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On 12/8/14, 1:05 PM, Robert Haas wrote:
> Besides, I haven't really seen anyone propose something that sounds
> like a credible alternative.  If we could make partition objects
> things that the storage layer needs to know about but the query
> planner doesn't need to understand, that'd be maybe worth considering.
> But I don't see any way that that's remotely feasible.  There are lots
> of places that we assume that a heap consists of blocks number 0 up
> through N: CTID pointers, index-to-heap pointers, nodeSeqScan, bits
> and pieces of the way index vacuuming is handled, which in turn bleeds
> into Hot Standby.  You can't just decide that now block numbers are
> going to be replaced by some more complex structure, or even that
> they're now going to be nonlinear, without breaking a huge amount of
> stuff.

Agreed, but it's possible to keep a block/CTID interface while doing something different on the disk.

If you think about it, partitioning is really a hack anyway. It clutters up your logical set implementation with a bunch of physical details. What most people really want when they implement partitioning is simply data locality.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting
Data in Trouble? Get it in Treble! http://BlueTreble.com


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