Database Reference
In-Depth Information
Figure 11.10. The revised relationship diagram that establishes the new business rule
Step 5: Determine What Actions Will Test the Rule
As you know, the constraint the business rule imposes is tested when you attempt to insert,
delete, or update a table record or field value. Now that you've established the business
rule and understand how it affects the relationship, determine what actions test the rule by
identifying whenaviolation oftheruleismostlikely tooccur.Usethefollowingquestions
to help you make your decision:
Are there circumstances under which this rule will be violated if I
enter a new record into this table?
Will this rule be violated if I do not enter a new record into this
table?
Will this rule be violated if I delete a record from this table?
Once you've determined which actions will trigger a violation of the rule, make note of
them; you'll use them in the next step. This information will also help you to establish
