global index internals

Can anyone point me at a description of how a global index works? The concepts manual says "a global partitioned index contains (conceptually) a single B*-tree with entries for all rows in all partitions. Each index partition may contain keys that refer to many different partitions or subpartitions in the table".

I guess this means you only need one index probe to get a rowid, but I don't understand how that can work when (I guess) the leaf blocks are in separate partitions without some kind of master area for the branch blocks, or at least the root block. Can anyone point me at a good description.

Thanks. Received on Wed Sep 03 2003 - 12:18:26 CDT