Re: GIST index : order Hack : getting the order used by CLUSTER .. USING my_index - Mailing list pgsql-general

From Rémi Cura
Subject Re: GIST index : order Hack : getting the order used by CLUSTER .. USING my_index
Date
Msg-id CAJvUf_uWwg55VgJF+P1TunUqN-S6_Qp=t8A6HEv9-EZyho6oHw@mail.gmail.com
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In response to Re: GIST index : order Hack : getting the order used by CLUSTER .. USING my_index  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: GIST index : order Hack : getting the order used by CLUSTER .. USING my_index  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
Hello,

I'm interested in the tree structure inherent to the gist indexing.
I was thinking to retrieve it from order of index.
Do you know how I could access it directly?

My use case would be to take advantage of this gist ordering to order 2D points
s1 : N1 N2 .. Nn 
so that for any given t<n,  s2 : [N1 Nt] points are an extract of s1 which is well spread (spatially speaking).

Ideally I would prefer to use the quadtree index in contrib rather than the Gist R Tree.

Cheers,

Rémi-C




2013/10/24 Tom Lane <tgl@sss.pgh.pa.us>
Rémi Cura <remi.cura@gmail.com> writes:
> I would like to be able to get the rows following the order of an index
> (*NOT* getting an order by accelerated, but only an order defined by an
> index).

Since a GiST index hasn't got any specific internal order, I fail to see
the point of this.

                        regards, tom lane

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