Database Reference
In-Depth Information
Figure 9-5. Taking a complex calculation one bite at a time helps you get the results you expect.
Just chip away at the parts and check your logic at each stage to make sure you and FileMaker are
in concert.
Using a Related Field in a Calculation
The invoice line items now calculate their extended prices automatically, because you cre-
ated a calculation at the beginning of the chapter to handle that. But you still have to add up
the extended price of each line item and enter the total amount due on the invoice itself.
Another calculation solves this problem:
1.
In the Jobs database, choose File
→
Manage
→
Databases and then go to the Fields
tab. From the Table pop-up menu, choose Invoices
.
The field list shows all the fields in the Invoices table.
2.
In the list, select the Total Due field
.
It's currently a Number field.
3.
From the Type pop-up menu, choose Calculation and then click the now high-
lighted Change button. When FileMaker asks if you're sure you want to make
this change (and replace any data in the field), click OK
.
The Specify Calculation dialog box pops up.
4.
From the View pop-up menu (above the function list), choose Aggregate Func-
tions
.
