Combining simultaneous values and temporal data dependencies

In temporal databases there are situations where multiple values of the same data item have overlapping validity times. In addition to the common case of multi-valued properties, there are several possible semantics to multiple values with overlapping validity times of the same data item. We refer to such data items as having simultaneous values. This paper presents a polynomial algorithm for efficient handling of simultaneous values in a database with temporal data dependencies-integrity rules that define relationships among values of different dated items in a temporal database. The algorithm is demonstrated using a case study from the game theory area. An implementation of the algorithm is integrated in a prototype of a temporal active database.