Abstract
We describe a formal design for a logical query language using psi-terms as data structures to interact effectively and efficiently with a relational database. The structure of psi-terms provides an adequate representation for so-called complex objects. They generalize conventional terms used in logic programming: they are sorted attributed structures, ordered thanks to a subsort ordering. Unification of psi-terms is an effective means for integrating multiple inheritance and partial information into a deduction process. We define a compact database representation for psi-terms, representing part of the subsorting relation in the database as well.
We describe a retrieval algorithm based on an abstract interpretation of the psi-term unification process and prove its formal correctness. This algorithm is efficient in that it incrementally retrieves only additional facts that are actually needed by a query, and never retrieves the same fact twice.
Original language | English |
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Title of host publication | Proceedings of the 11th International Conference on Logic Programming (ICLP 1994) |
Place of Publication | Cambridge, MA, USA |
Publisher | MIT Press |
Pages | 437-455 |
Number of pages | 19 |
ISBN (Print) | 0-262-72022-1 |
Publication status | Published - Jun 1994 |
Event | 11th International Conference on Logic Programming, ICLP 1994 - Santa Margherita Ligure, Italy Duration: 13 Jun 1994 → 18 Jun 1994 Conference number: 11 |
Conference
Conference | 11th International Conference on Logic Programming, ICLP 1994 |
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Abbreviated title | ICLP |
Country/Territory | Italy |
City | Santa Margherita Ligure |
Period | 13/06/94 → 18/06/94 |
Keywords
- DB-OODB: OBJECT-ORIENTED DATABASES
- DB-DDB: DEDUCTIVE DATABASES