Learn More
Query processing can be sped up by keeping frequently accessed users' views materialized. However, the need to access base relations in response to queries can be avoided only if the materialized view is adequately maintained. We propose a method in which all database updates to base relations are first filtered to remove from consideration those that(More)
Consider a database containing not only base relations but also stored derived relations (also called materialized or concrete views). When a base relation is updated, it may also be necessary to update some of the derived relations. This paper gives sufficient and necessary conditions for detecting when an update of a base relation cannot affect a derived(More)
T he Zeitgeist object-oriented database management systems, developed by Texas Instruments between 1985 and 1990,' supported applications in computer-aided design and manufacturing, software engineering, knowledge representation, and hypermedia systems. From the Zeitgeist project, we learned that these applications have widely varying database management(More)
Traditional client-server applications relegate query and persistence operations on their data to database systems. The database system operates on data in the form of rows and tables, while the application operates on data in terms of higher-level programming language constructs (classes, structures etc.). The <i>impedance mismatch</i> in the data(More)
This paper reports our experiences building the query optimizer for TI's Open OODB system. To the best of our knowledge, it is the first working object query optimizer to be based on a complete extensible optimization framework including logical algebra, execution algorithms, property enforcers, logical transformation rules, implementation rules, and(More)
The integration of the .NET Common Language Runtime (CLR) into the SQL Server DBMS enables rich business logic written in modern .NET languages to run close to the data. Database application developers can write business logic as functions, stored procedures, and triggers. They can also extend the native capabilities of the DBMS by adding new scalar data(More)
Active OODBMSs must provide eecient support for event detection, composition, and rule execution. Previous experience, reported here, building active capabilities on top of existing closed OODBMSs has proven to be ineeective. We propose instead an active OODBMS architecture where event detection and rule support are tightly integrated with the rest of the(More)
paper is concerned with ways of specifying situations and evaluating them efficiently. The techniques described in this paper were developed as part of the HiPAC (High Performance Active) DBMS. a prototype active DBMS (DAYA88a. DAYA88b. CHAK89], parts of which have been implemented. However. the algebra and transformations described in this paper can be(More)