A Visual Query Language for Temporal Databases a Visual Query Language for Temporal Databases

This paper addresses the issue of visual query formulation for temporal databases. We introduce a number of visual constructs that allow users to build queries in a modular, bottom{up fashion based on a temporal Extended Entity{Relationship Model. These constructs are: Temporal projection, temporal selection, time links, ltering and set operators, and temporal aggregates. This paper also identiies the main challenges posed by visual interface design for temporal databases. It presents guidelines for designing user{friendly, exible visual environment for temporal design editors, temporal query editors, temporal update editors, and temporal display editors.