The temporal database is a database that can keep information on time when the facts represented in the database were, are, or will be valid. We briefly described major concepts of temporal databases and discussed types of queries that such databases can support in part 1 of this article series. The content of part 1 is essential for understanding the part 2.
In this part 2 we discuss what kind of aggregates can be obtained from a temporal database and how to express these aggregations in the SQL language. The examples in the part 2 are based on table definitions