On Thu, Aug 29, 2019 at 8:22 PM Alexander Korotkov <a.korot...@postgrespro.ru> wrote: > Alternatively you can encode size in Z-value. But this increases > dimensionality of space and decreases efficiency of join. Also, > spatial join can be made using two indexes, even just current GiST > without Z-values. We've prototyped that, see [1].
I'm pretty sure that spatial joins generally need two spatial indexes (usually R-Trees). There seems to have been quite a lot of research in it in the 1990s. -- Peter Geoghegan
