Manfred Koizar <mkoi-pg@aon.at> writes:
> ... where "similar" means that the value of each attribute lies within
> a small range around the value of the corresponding attribute of the
> reference object?
> I don't know, whether GiST or R-Tree could help.
If the problem is multidimensional range search then GIST might be just
the ticket. I am not sure if you'd need to do any coding though. It
looks like contrib/btree_gist provides the necessary operator class, but
only for int4 and timestamp datatypes.
I think that our r-tree code is restricted to two-dimensional indexing,
so it wouldn't help.
regards, tom lane