Database Reference
In-Depth Information
A single record in the AGENTS table can be associated with no more than 25 re-
cords in the ENTERTAINERS table.
•
Type:
Here is where you indicate whether the rule is database oriented or applica-
tion oriented.
•
Category:
This is where you indicate whether the rule is field specific or relation-
ship specific.
•
Test On:
Here is where you indicate which actions (insert, delete, update) will test
the constraint the business rule imposes.
•
Structures Affected:
Depending on the type of business rule, the constraint will af-
fect either a field or a relationship. This is where you designate the name of the
field(s) the rule will affect or the name of the table(s) involved in the relationship
that the rule affects.
•
Field Elements Affected:
A business rule that pertains to a field can affect one or
more elements of that field's specifications. This is where you indicate the ele-
ments the rule affects.
•
Relationship Characteristics Affected:
A business rule that pertains to a relation-
ship will affect one or more of the relationship's characteristics. Here is where you
indicate the characteristics that the rule affects.
•
Action Taken:
Here you indicate the modifications you've made to the elements of
a field specification or to a relationship diagram. It is very important that the state-
ment you enter here be as clear and unambiguous as possible. Should a problem
occur as a result of enforcing this business rule, this statement serves as accurate
documentation of the steps you have taken to establish the rule. You can use this
statement to make certain that these steps were actually carried out and that the
rule has been properly established.
Now, fill out a Business Rule Specifications sheet for the rule you established in Step 4.
Figure11.8
showsacompletedBusinessRuleSpecificationssheetthatdocumentsthebusi-
ness rules you established for the C
UST
C
OUNTY
field.
