Abstract: As Internet is being widely and deeply used,Internet has become a vast repository of online information resources．It is essential herein to enable end-users to develop situational data integration applications by themselves,and thus to profit from the online information resources’ potential value．The paper presented a user-steered situational data integration environment called data service space(DSS),which supports the most current used network resources,implements the ability to personalized wrap HTML Web page interactively,combines spreadsheet programming style and nested relational model,provides a set of visualized nested table operators and formula language,offers required agility and expressive power to support situational data integration by non-professional users．Use case and related work analysis reveal the potentials of DSS in situational data integration.

Key words: Data integration,Data service,Situational application,Mashup