TY - BOOK
T1 - Extending OLAP Querying to External Object
AU - Pedersen, Torben Bach
AU - Shoshani, Arie
AU - Gu, Junmin
AU - Jensen, Christian Søndergaard
PY - 2000
Y1 - 2000
N2 - On-Line Analytical Processing (OLAP) systems based on a dimensional view of data have found widespread use in business applications and are being used increasingly in non-standard applications. These systems provide good performance and ease-of-use. However, the complex structures and relationships inherent in data in nonstandard applications are not accommodated well by OLAP
systems. In contrast, object database systems are built to handle such complexity, but do not support OLAP-type querying well. This paper presents the concepts and techniques underlying a flexible, multi-model federated system that enables OLAP users to exploit simultaneously the features of OLAP and object systems. The system allows data to be handled using the most appropriate data model and technology: OLAP systems for dimensional data and object database systems for more complex, general data. Additionally, physical data integration can be avoided. As a vehicle for demonstrating the capabilities of the system, a
prototypical OLAP language is defined and extended to naturally support queries that involve data in object databases. The language permits selection criteria
that reference object data, queries that return combinations of OLAP and object data, and queries that group dimensional data according to object data. The system is designed to be aggregation-safe, in the sense that it exploits the aggregation semantics of the data to prevent incorrect or meaningless query results. These capabilities may also be integrated into existing languages. A prototype implementation of the system is reported.
AB - On-Line Analytical Processing (OLAP) systems based on a dimensional view of data have found widespread use in business applications and are being used increasingly in non-standard applications. These systems provide good performance and ease-of-use. However, the complex structures and relationships inherent in data in nonstandard applications are not accommodated well by OLAP
systems. In contrast, object database systems are built to handle such complexity, but do not support OLAP-type querying well. This paper presents the concepts and techniques underlying a flexible, multi-model federated system that enables OLAP users to exploit simultaneously the features of OLAP and object systems. The system allows data to be handled using the most appropriate data model and technology: OLAP systems for dimensional data and object database systems for more complex, general data. Additionally, physical data integration can be avoided. As a vehicle for demonstrating the capabilities of the system, a
prototypical OLAP language is defined and extended to naturally support queries that involve data in object databases. The language permits selection criteria
that reference object data, queries that return combinations of OLAP and object data, and queries that group dimensional data according to object data. The system is designed to be aggregation-safe, in the sense that it exploits the aggregation semantics of the data to prevent incorrect or meaningless query results. These capabilities may also be integrated into existing languages. A prototype implementation of the system is reported.
M3 - Book
T3 - Technical Report
BT - Extending OLAP Querying to External Object
PB - Aalborg Universitetsforlag
CY - Department of Computer Science
ER -