[postgis-devel] Caching Double-based Boxes

[Nicklas Avén]

> > There is nothing that points to the index key from the geometry? Is it
> > so. It is the same reason we can't get the extent from a table from the
> > index?
> 
> I'd think you could, altought not easily.
> 

interesting

> But the main reason why you don't want to do that is that you don't
> want to be _forced_ to have an index in order to process values.
> Note that Geometry values could also be literal, never touching a table.
> 

Yes, but if the geometry is literal the extra cost of calculating the
bbox seems very very small. That calculation could in that case be done
when building a geometry from text. Then all coordinates is traversed
anyway.

If the index would be the only place where the boxes was stored/cached
it would just mean that without an index the boxes will have to be
calculated each time.

If this would be possible I will vote for that in PostGIS 3 :-)

/Nicklas




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