A Table Presentation Language for Database Applications

Abstract

Database applications often utilize a large number of reports. There are tools, report generators, as well as programming-level supports that facilitate the generation of reports. However, these supports are restricted to simple predefined presentation formats with limited flexibility. In general, a report consists of one or more data sources, which are not necessarily stored in formats that are ready for presentation. Therefore programmers must write application programs to convert query results into suitable presentation formats. In particular, the aim is to place the right data into the right position so that the report is easy to understand. Since the results of a query are inherently tabular, by restricting the reports into tabular formats, the problem reduces to the transformation of data between tables. This paper studies how the position of one data is transferred to another. We characterize and formulate fundamental transformations into high-level transformation operations, including normal, transpose, fill, combine, and matching. We then propose a high-level Table Presentation Language (TPL) to realize these operations. TPL can be used to create sophisticated reports without the overhead of writing tedious low-level programs. Therefore the complexity of generating reports is greatly reduced. We have used TPL to construct several web-based database applications. In our experience, it is convincing that the language is very useful and practical for creating database query and report applications.