Digital Symposium Collection 2000

Integrating Heterogenous Overlapping Databases through Object-Oriented Transformations Vanja Josifovski and Tore Risch   View Paper (PDF)   Return to Integrating Heterogeneous Databases Abstract Integration of data from autonomous and heterogeneous data sources often requires means to mediate and reconcile overlaps and conflicts between the integrated data. It is also desirable that the mediator system stores local data associated with the data from the sources. Achieving acceptable query response time for a mediator system has been a known research problem. This work presents a mediator query processing framework based on a representation of the data mediation and reconciliation by a number of auxiliary system-defined object-oriented (OO) views and overloaded functions (queries). The framework is supported by defining an overloading and late binding mechanism for the OO views through declarative queries. A query over the mediated OO views will have late bound subquery invocations which are transformed into disjunctive query expressions. Consistency and completeness of the queries are guaranteed by expanding the queries with validation subqueries. Performance is improved by type aware query rewrites and selective OID generation in the mediators. Experiments show that the proposed query optimization dramatically improves the query execution time compared to a naive instance-oriented query strategy or partial strategies. References Note: References link to DBLP on the Web. [1] Elisa Bertino : A View Mechanism for Object-Oriented Databases. EDBT 1992 : 136-151 [2] Omran A. Bukhres , Ahmed K. Elmagarmid (Eds.): Object-Oriented Multidatabase Systems: A Solution for Advanced Applications. Prentice-Hall 1996, ISBN 1-13-103813-3 [3] ... [4] Umeshwar Dayal , Hai-Yann Hwang : View Definition and Generalization for Database Integration in a Multidatabase System. TSE 10(6) : 628-645(1984) [5] ... [6] Gustav Fahl , Tore Risch : Query Processing Over Object Views of Relational Data. VLDB Journal 6(4) : 261-281(1997) [7] Doug Fang , Shahram Ghandeharizadeh , Dennis McLeod , Antonio Si : The Design, Implementation, and Evaluation of an Object-Based Sharing Mechanism for Federated Database Systems. ICDE 1993 : 467-475 [8] Staffan Flodin , Tore Risch : Processing Object-Oriented Queries with Invertible Late Bound Functions. VLDB 1995 : 335-344 [9] Hector Garcia-Molina , Yannis Papakonstantinou , Dallan Quass , Anand Rajaraman , Yehoshua Sagiv , Jeffrey D. Ullman , Vasilis Vassalos , Jennifer Widom : The TSIMMIS Approach to Mediation: Data Models and Languages. JIIS 8(2) : 117-132(1997) [10] Laura M. Haas , Donald Kossmann , Edward L. Wimmers , Jun Yang : Optimizing Queries Across Diverse Data Sources. VLDB 1997 : 276-285 [11] ... [12] ... [13] Vanja Josifovski , Tore Risch : Functional Query Optimization over Object-Oriented Views for Data Integration. JIIS 12(2-3) : 165-190(1999) [14] Ee-Peng Lim , San-Yih Hwang , Jaideep Srivastava , Dave Clements , M. Ganesh : Myriad: Design and Implementation of a Federated Database Prototype. SP&E 25(5) : 533-562(1995) [15] Witold Litwin , Tore Risch : Main Memory Oriented Optimization of OO Queries Using Typed Datalog with Foreign Predicates. TKDE 4(6) : 517-528(1992) [16] ... [17] David W. Shipman : The Functional Data Model and the Data Language DAPLEX. TODS 6(1) : 140-173(1981) [18] Anthony Tomasic , Louiqa Raschid , Patrick Valduriez : Scaling Access to Heterogeneous Data Sources with DISCO. TKDE 10(5) : 808-823(1998) [19] Gio Wiederhold : Mediators in the Architecture of Future Information Systems. IEEE Computer 25(3) : 38-49(1992) BIBTEX @inproceedings{DBLP:conf/vldb/JosifovskiR99,   author    = {Vanja Josifovski and                 Tore Risch},    editor    = {Malcolm P. Atkinson and                 Maria E. Orlowska and                 Patrick Valduriez and                 Stanley B. Zdonik and                 Michael L. Brodie},    title     = {Integrating Heterogenous Overlapping Databases through Object-Oriented                 Transformations},    booktitle = {VLDB'99, Proceedings of 25th International Conference on Very                 Large Data Bases, September 7-10, 1999, Edinburgh, Scotland,                 UK},    publisher = {Morgan Kaufmann},    year      = {1999},    isbn      = {1-55860-615-5},    pages     = {435-446},    crossref  = {DBLP:conf/vldb/99},    bibsource = {DBLP, http://dblp.uni-trier.de} } }, Copyright(C) 2000 ACM