I want to construct an "Composite Index Structure" i.e. a combination of gist and btree. What i am thinking is that first creating a Rtree structure that is pointing to another Btree structure. For example, Suppose i want to find vehicles between 2 to 4 pm on 14/2/2011 on X road.
I am thinking of creating rtree structure for road network and then btree for time. For reaching X road i use Rtree, and from there btree begin i.e. leaf node of rtree contains the pointer to root node of btree ( in this way i have all time belonging to X road)
My question is that how to implement this composite index structure in postgres?
Let us suppose, if i create mygist index, then i have to write my own operator class? or can i use gist index as it is and btree tree as it is. I mean their operator class and their gist methods but how to establish linkage between them?