Re: SP-GiST for ranges based on 2d-mapping and quad-tree

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:
> On 29.07.2012 00:50, Tom Lane wrote:
>> We could possibly extend the API to allow a different type to be used
>> for this, but then it wouldn't be "reconstructed data" in any sense of
>> the word; so I think it'd be abuse of the concept --- which would come
>> back to bite us if we ever try to support index-only scans with SPGiST.

> I can see that for leaf nodes, but does that also hold for inner nodes?

I didn't explain myself terribly well, probably.  Consider an opclass
that wants some private state like this and *also* needs to reconstruct
column data.

In principle I suppose we could do away with the reconstructed-data
support altogether, and consider that if you need that then it is just a
portion of the unspecified private state the opclass is holding.  But
it's probably a bit late to remove bits of the opclass API.
        regards, tom lane