Interval Queries on Object Histories : Extended

This extended abstract introduces the notion of ’ interval queries ’ on historical data for objects (here, called ‘object histories’) and explores a certain closure property. As for describing historical data for objects, we use our mathematical model introduced in our earlier paper. The major construct in the model is a ‘computation-tuple sequence scheme’ (abbreviated CSS), which specifies the set of all possible ‘valid’ object histories for the same type of object. Interval queries are those queries which return an interval (history) from a given object history. We provide conditions under which an interval query applied to object histories described by one CSS yields, as its answers. the set of all object histories which can be described by another CSS.