On querying spreadsheets

Considers the problem of querying the data in applications such as spreadsheets and word processors. This problem has several motivations from the perspective of data integration, interoperability and OLAP. We provide an architecture for realizing interoperability among such diverse applications and address the challenges that arise specifically in the context of querying data stored in spreadsheet applications. A fundamental challenge is the lack of a well-defined schema. We propose a framework in which the user can specify the layout of data in a spreadsheet, based on his perception of the important concepts underlying that data. Layout specifications can be viewed as the "physical schema" of a spreadsheet. We motivate the concept of an abstract database machine (ADM) that uses the layout specifications to provide a relational view of the data in spreadsheet applications and, similar to a DBMS, supports efficient querying of the spreadsheet data. We develop a methodology for building ADMs for spreadsheets and describe our implementation of an ADM for Microsoft Excel applications, based on the above methodology. Our implementation platform is IBM PCs running Windows NT, Microsoft Office and OLE 2.0. We demonstrate the generality and practicality of our approach by developing a formal characterization of the class of spreadsheets that can be handled in our framework. Our results show that the approach is capable of handling a broad class of naturally occurring spreadsheet applications. This work is part of an office tool integration project.