The R*-tree: an efficient and robust access method for points and rectangles
SIGMOD '90 Proceedings of the 1990 ACM SIGMOD international conference on Management of data
SIGMOD '91 Proceedings of the 1991 ACM SIGMOD international conference on Management of data
Shoring up persistent applications
SIGMOD '94 Proceedings of the 1994 ACM SIGMOD international conference on Management of data
COBRA fundamentals and programming
COBRA fundamentals and programming
The object database standard: ODMG 2.0
The object database standard: ODMG 2.0
Xmas: an extensible main-memory storage system for high-performance applications
SIGMOD '98 Proceedings of the 1998 ACM SIGMOD international conference on Management of data
Distributed object computing platforms
Communications of the ACM
Communications of the ACM
R-trees: a dynamic index structure for spatial searching
SIGMOD '84 Proceedings of the 1984 ACM SIGMOD international conference on Management of data
Proceedings of the Second International Conference on Interoperating Geographic Information Systems
INTEROP '99 Proceedings of the Second International Conference on Interoperating Geographic Information Systems
ICDE '98 Proceedings of the Fourteenth International Conference on Data Engineering
Proceedings of the 17th International Conference on Data Engineering
Cache-Conscious Concurrency Control of Main-Memory Indexes on Shared-Memory Multiprocessor Systems
Proceedings of the 27th International Conference on Very Large Data Bases
Multiview: A Methodology for Supporting Multiple Views in Object-Oriented Databases
VLDB '92 Proceedings of the 18th International Conference on Very Large Data Bases
SchemaSQL - A Language for Interoperability in Relational Multi-Database Systems
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Reasoning about Binary Topological Relations
SSD '91 Proceedings of the Second International Symposium on Advances in Spatial Databases
Spatial Internet Marketplaces: A Grand Challenge?
SSD '97 Proceedings of the 5th International Symposium on Advances in Spatial Databases
INTEROP '99 Proceedings of the Second International Conference on Interoperating Geographic Information Systems
Building a Prototype OpenGIS Demonstration from Interoperable GIS Components
INTEROP '99 Proceedings of the Second International Conference on Interoperating Geographic Information Systems
Towards heterogeneous multimedia information systems: the Garlic approach
RIDE '95 Proceedings of the 5th International Workshop on Research Issues in Data Engineering-Distributed Object Management (RIDE-DOM'95)
Hi-index | 0.01 |
With the proliferation of various geographic databases on the Internet, we have seen increasing needs for accessing them concurrently and remotely via the Web for high-level decision making. In this paper, we present Middleware for Efficient Access to Databases through OpenGIS Wrappers (MEADOW), an object-oriented middleware system we have developed to meet these needs. Current OpenGIS standard addresses many interoperability issues involved in such a global utilization of geographic databases. However, existing Simple Feature specification for CORBA (SFCORBA) implementations of OpenGIS proved to be insufficient for MEADOW. The main problems are the complexity of system development and maintenance, and the inefficiency of accessing remote data servers for processing region queries. We resolved the complexity problem by automatically generating a major portion of the application code, specifically wrappers on database servers and client library modules called transparent access providers. A MEADOW view definition language was developed as a high-level specification language for this purpose. The efficiency problem was resolved by using a region-based group prefetching of spatial objects from a geographic region. In addition, we implemented an OID-based semijoin for efficient global query processing, and a region-level locking to enhance the level of concurrency among region queries.