Data warehousing and on-line analytical processing (OLAP) are essential for decision support applications. Common OLAP operations include for example drill down, roll up, pivot an...
We investigate the problem of using materialized views to answer SQL queries. We focus on modern decision-support queries, which involve joins, arithmetic operations and other (po...
Markos Zaharioudakis, Roberta Cochrane, George Lap...
In this paper we introduce generalized projections (GPs), an extension of duplicateeliminating projections, that capture aggregations, groupbys, duplicate-eliminating projections ...
A data warehouse DW can be seen as a set of materialized views de ned over remote base relations. When a query is posed, it is evaluated locally, using the materialized views, wi...
In this paper we propose a mediator architecture for the querying and integration of Web-accessible XML data sources. Our contributions are (i) the definition of a simple but expr...