R-tree indexing

[Doug Welch <welch@physics.mcmaster.ca>]

Two questions:

1) Is R-tree indexing being used on coordinate boxes of type box?
If not, this would be a superb idea since R-tree indexed coordinate
box queries (overlap, contained-within, etc) are viciously efficient
and postgresql implements this index.

2) Is anyone considering implementing an "alert" query which would
be triggered by a object being added outside previous object positions
(if they exist for that part of the sky) and/or not in the Tycho list?
This would be a way of detecting moving objects, flare stars, novae,
etc.

Cheers,
Doug