[postgis-users] Fast way of finding comon points

[Jason R. Moore]

I would like to know if their is a fast way of finding points common to 
two geoms. 
What have are the tiger line files in a data base with each county in 
it's own table and I have created source and destination columns using 
pgdijkstra-0.3 and would like to merge them into one table and update 
the source and destination column where the lines inter sect. 
Correct me if i am wrong but this should be fairly fast because the 
inter sections only occur on county line boundaries which should lend 
it's self to some sort of bounding box... I am finding that Implementing 
this is not so trivial.


Jason R. Moore