A Temporal Logic for Supporting Historical Databases

Abstract.

Tackling data with gap-interval time is an important issue faced by the temporal database community. While a number of interval logics have been developed, less work has been reported on gap-interval time. To represent and handle data with time, a clause ‘when’ is generally added into each conventional operator so as to incorporate time dimension in temporal databases, which clause ‘when’ is really a temporal logical sentence. Unfortunately, though several temporal database models have dealt with data with gap-interval time, they still put interval calculus methods on gap-intervals. Certainly, it is inadequate to tackle data with gap-interval time using interval calculus methods in historical databases. Consequently, what temporal expressions are valid in the clause ‘when’ for tackling data with gap-interval time? Further, what temporal operations and relations can be used in the clause ‘when’? To solve these problems, a formal tool for supporting data with gap-interval time must be explored. For this reason, a gap-interval-based logic for historical databases is established in this paper. In particular, we discuss how to determine the temporal relationships after an event explodes. This can be used to describe the temporal forms of tuples splitting in historical databases.