Assume the individual transactions have the following characteristics:
| Times | Increase Order Transaction | Reduce Discount Transaction |
|---|---|---|
| Begin Time | 2009-01-05 | 2009-01-02 |
| Modification Time | 2009-01-10 | 2009-01-03 |
| End Time | 2009-01-11 | 2009-01-04 |
Notice that Reduce Discount ends before Increase Order begins.
The following shows the states of the Parts and Orders tables after transactions have completed.
Parts Table after the Reduce Discount transaction:
| Part_ID | Supplier_ID | Price | Discount | Part_Validity |
|---|---|---|---|---|
| P1 | S1 | $10 | 10% | (2008-01-01, 2009-01-02) |
| P1 | S1 | $10 | 5% | (2009-01-02, 2011-01-01) |
In the original state of the tables, the P1 rows qualified for the CURRENT transaction because their valid times overlapped TEMPORAL_DATE.
Additionally, the P1 row in the Parts table was modified, because the P1 row in the Orders table fulfilled the transaction WHERE test (quantity < 100).
The modification of the P1 row in the Parts table leaves a history row showing the state of the row prior to the modification. Notice the end time of the first row and the beginning time of the second row have both been timestamped with TEMPORAL_DATE at the time of the modification.
Orders table after Increase Order transaction:
| Order_ID | Part_ID | Quantity | Order_Validity |
|---|---|---|---|
| O1 | P1 | 60 | (2008-01-01, 2011-01-01) |
The row was not changed, because the current time at the time of the Increase Order transaction was 2009-01-05. Using this current time, only the second row in the Parts table qualifies for the transaction, however that row fails the WHERE test (discount >= 10), due to the changes made by the preceding Reduce Discount transaction.