Database Reference
In-Depth Information
Figure 5-17. Here you see the Specify Field dialog box's Current Table menu popped up, with a list
of all the table occurrences on the graph. The ones related to the current layout are at the top, and
all unrelated tables are grouped below. Right now you don't have any unrelated tables because the
entire graph is connected in one group. The <<Expense>> merge field you're editing is visible be-
hind the Specify Field window.
As you flip through the records, you'll see that the first few expenses show a Job name.
That's because the sample database had Expense records with Job ID values in them, and
once you defined the relationships, the proper records were linked. But how do you go about
entering a valid Job ID into an Expense record as you log expenses? That's where
value lists
come in.
Creating a Value List Based on a Related Field
You've already seen value lists based on custom values—on
Adding a Field Control Style
and a Value List
,
you created a value list to make sure only certain values were entered in the
Lease Duration field. In a relational database, valid data entry is even more critical, particu-
larly when you're not using a portal to create related records. Remember, a portal automatic-
ally adds the primary key value to the child table when you create a related record; that way
the proper foreign key value is created in the to-many side of the relationship.
