Query modification in object-oriented database federations

We discuss the modification of queries against an integrated view in a federation of object-oriented databases. We present a generalisation of existing algorithms for simple global query processing that works for arbitrarily defined integration classes. We then extend this algorithm to deal with object-oriented features such as queries involving path expressions and nesting. We show how properties of the OO-style of modelling relationships through object references can be exploited to reduce the number of subqueries necessary to evaluate such queries.

[1]  Umeshwar Dayal,et al.  Query Processing in a Multidatabase System , 1985, Query Processing in Database Systems.

[2]  Dennis McLeod,et al.  A federated architecture for information management , 1985, TOIS.

[3]  Peter M. G. Apers,et al.  Semantic Query Optimization in Distributed Databases , 1991, ICCI.

[4]  Peter M. G. Apers,et al.  The Role of Integrity Constraints in Database Interoperation , 1996, VLDB.

[5]  Herman Balsters,et al.  Typed Sets as a Basis for Object-Oriented Database Schemas , 1993, ECOOP.

[6]  Peter M. G. Apers,et al.  Behaviour Specification in Database Interoperation , 1997, CAiSE.

[7]  Setrag Khoshafian.  Object orientation , 1990 .

[8]  Dennis McLeod,et al.  An experimental object-based sharing system for networked databases , 1996, The VLDB Journal.

[9]  Patrick Valduriez,et al.  Distributed and parallel database systems , 1996, CSUR.

[10]  Peter M. G. Apers,et al.  On the Applicability of Schema Integration Techniques to Database Interoperation , 1996, ER.

[11]  Arbee L. P. Chen,et al.  A mapping strategy for querying multiple object databases with a global object schema , 1995, Proceedings RIDE-DOM'95. Fifth International Workshop on Research Issues in Data Engineering-Distributed Object Management.

[12]  Jaideep Srivastava,et al.  Entity identification in database integration , 1993, Proceedings of IEEE 9th International Conference on Data Engineering.

[13]  Umeshwar Dayal,et al.  View Definition and Generalization for Database Integration in a Multidatabase System , 1984, IEEE Transactions on Software Engineering.

[14]  Arbee L. P. Chen.  Outerjoin optimization in multidatabase systems , 1990, DPDS '90.

[15]  Clement T. Yu,et al.  Query Processing in Multidatabase Systems , 1995, Modern Database Systems.

[16]  Ahmed K. Elmagarmid,et al.  Object orientation in multidatabase systems , 1995, CSUR.

[17]  Patrick Valduriez,et al.  A Methodology for Query Reformulation in CIS Using Semantic Knowledge , 1996, Int. J. Cooperative Inf. Syst..

[18]  Patrick Valduriez,et al.  Query Reformulation in Multidatabase Systems using Semantic Knowledge , 1994 .