Enhancement of Query Access Optimization by Functional Dependencies
Original Publication Date: 1986-Dec-01
Included in the Prior Art Database: 2005-Mar-09
To assist in the optimization of access in a data base query system, particularly one employing Access Independent Query Definition (AIQD), given a particular path definition defined for a query, it is first expanded by adding segments, then transformed into any path that has the same query structure, and then eroded by subtracting segments. As described in AIQD, the selection of a segment in an Entry Data Base (EDB) may be used to determine a number of paths (as defined in Program Communication Blocks (PCBs) which have a common query structure. The possession of such a common query structure by a set of paths means that any query defined on any one of those paths may be executed using any other path in the set.