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Managing Time in Relational Databases by Randall Weis, Tom Johnston

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14. Allen Relationship and Other Queries
Allen Relationship Queries313
Time Period to Time Period Queries316
Point in Time to Period of Time Queries333
Point in Time to Point in Time Queries341
A Claims Processing Example343
In Other Words346
Glossary References347
In this chapter, we examine each of the thirteen Allen relationships, as well as each non-leaf node in the taxonomy of Allen relationships which we introduced in Chapter 3. We describe the Allen relationships as they hold between two time periods, between a time period and a point in time, and also between two points in time. We show how these relationships are expressed in terms of time periods represented with the closed-open convention, and we provide a sample query for each one.
After ...

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