We give a simple transformation from normal programs with no stratification (local, weak, modular, etc.) into a subclass of the locally stratified programs, called Explicitly Locally Stratified (ELS) programs, for which there are efficient evaluation techniques. One set of predicates are generated for the true tuples and a different set of predicate are generated for the true and undefined tuples. A similar transformation is given that incorporates a magic sets like transformation. Previous approaches to magic sets transformations of unstratified programs either restricted the class of sips used or generated a program that required special treatment of the magic sets predicates. Our transformation does not suffer from these flaws.
|Number of pages||40|
|Journal||Journal of Systems Integration|
|Publication status||Published - 1 Dec 1997|
- Deductive databases
- Explicitly locally stratified
- Logic programming
- Magic sets