[postgis-devel] Implement New Geometry Index Method?

[Rémi Cura]

2014-05-21 21:02 GMT+02:00 Jeremy Palmer <JPalmer at linz.govt.nz>:

>
> > As a side not
> > _ in your first use case, you could have forced the use of index by
> adding to the intersect :
> > AND admin.geom && other.geom,
> > or even computing this as a first step.
>
> I thought ST_Intersect just expanded to "SELECT $1 && $2 AND
> _ST_Intersects($1,$2)"
>

Yep,  but it seems that the bounding box was not used in your case

>
> > _your admlinistrativ limit seems to be a partition of the space (no
> overlaping). In this case there exist very fast way to get the intersect
> answer, but it is not used in GIS field.
>
> Interesting. Do you have a reference to this method?


This is called a topology model, or a 2D Arrangment more formaly.
See for instance
http://doc.cgal.org/latest/Arrangement_on_surface_2/group__PkgArrangement2.html
Or PostGIS Topology ( not performance-oriented).

Cheers,
Rémi-C
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