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Temporal Database. Chap 3: The Interval-extended Relational Model and Its Applications to Valid-time Databases. 3.2 Underlying Formalization. 3.2 Underlying Formalization. 3.2 Underlying Formalization. The empty set is not an interval.
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Temporal Database Chap 3: The Interval-extended Relational Model and Its Applications to Valid-time Databases
3.2 Underlying Formalization The empty set is not an interval. Boundaries of interval: start(:di, dj)) stop(:di, dj)) I(D): The set of all the intervals over 1-d space D
3.2.3 N-Dimensional Intervals du =:2,6) × :1,6)
3.3.2 Operations Union, Difference, Projection, Cartesian Product
3.3.2 Operations S = Fold: Ai ! ( R )
3.3.2 Operations IF S = Fold: Ai! ( R ) , the following properties are satisfied.
3.3.2 Operations R = Unfold: Time ! (SALARY) SALARY = Fold: Time! (R) 3.3.2 Operations
3.3.3 Geometric Interpretation of the New Operations
3.3.3 Geometric Interpretation of the New Operations
3.3.3 Geometric Interpretation of the New Operations
3.3.3 Geometric Interpretation of the New Operations
3.3.3 Geometric Interpretation of the New Operations