Name
Abstract | ||
|---|---|---|
In order to extend the expressive power of deductive databases, a formula that can have existential quantifiers in prenex normal form in a restricted way is defined as an extended rule. With the extended rule, we can easily define a virtual view that requires a division operation of relational algebra to evaluate. The paper addresses a recursive query evaluation where at least one formula in a recursive rule set is of an extended rule. We investigate transformable recursions as well as four cases of non-transformable recursions of transitive-closure-like and linear type. The work reveals that occurrence of an existentially quantified variable in the extended recursive body predicate might dramatically limit the level of recursive search. In particular, the number of iterations to answer extended queries can be determined, independently of database contents |
Year | DOI | Venue |
|---|---|---|
1995 | 10.1109/69.382302 | IEEE Trans. Knowl. Data Eng. |
Keywords | Field | DocType |
existential quantifiers,database content,existentially quantified variable,extended recursive body predicate,non-transformable recursions,extended query,extended rules,extended rule,nontransformable recursions,recursive query evaluation,expressive power,transformable recursions,relational algebra,recursive queries,linear recursions,deductive databases,database theory,extended queries,transitive-closure-like recursions,recursive search,iterations,recursive rule set,prenex normal form,virtual view,division operation,iterative methods,query processing,artificial intelligence,dbms,normal form,null value,relation algebra,sections,transitive closure,automated reasoning,algebra,indexing terms | Data mining,Automated reasoning,Deductive database,Recursive set,Computer science,Prenex normal form,Theoretical computer science,Relational algebra,Database theory,Transitive closure,Database,Recursion | Journal |
Volume | Issue | ISSN |
7 | 2 | 1041-4347 |
Citations | PageRank | References |
7 | 11.67 | 6 |
Authors | ||
2 | ||
Name | Order | Citations | PageRank |
|---|---|---|---|
| Sang Ho Lee | 1 | 182 | 102.61 |
| Lawrence J. Henschen | 2 | 478 | 280.94 |