Situational data integration with data services and nested table

Situational data integration is often ad hoc, involves active participation of business users, and requires just-in-time treatment. Agility and end-user programming are of importance. The paper presents a spreadsheet-like programming environment called Mashroom, which offers required agility and expressive power to support situational data integration by non-professional users. In Mashroom, various data sources are encapsulated as data services with nested tables as their unified data model both for internal processing and for external uses. Users can operate on the nested tables interactively. Mashroom also supports the basic control flow patterns. The expressive power of Mashroom is analyzed and proved to be richer than N1NF relational algebra. All the XQuery expressions can be mapped to Mashroom operations and formulas. Experiments have revealed the potentials of Mashroom in situational data integration.