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Update and insert into temporal child table, delete from parent table These three scenarios differ in complexity for RI checking, and as a result, the measured overhead also ranges 15.17% - 60.03%, as shown in Figure 7-22. 

<img src='content_image/984489.jpg'>

## Db2 enforced RI checking versus trigger enforced RI checking 

To determine how efficient Db2 engine code is to enforce the RI relationship between parent and child tables, we performed an experiment in which a row was inserted into a temporal child table with Db2 enforced RI checking versus inserting that row into a child temporal table where the RI is enforced by using triggers. The trigger that was used in this scenario is shown in Example 7-31. 

<img src='content_image/984488.jpg'>

