Operation Manual

d) Select Delete cascade.
e) Click OK to close the Relations dialog and choose File > Save to save the Relation
Design window.
While these options are not strictly necessary, they do help. Having them selected permits
you to update a table that has a relationship defined with another table which has been
modified. It also permits you to delete a field from the table without causing inconsistencies.
Creating a database form
Databases are used to store data. But, how is the data put into the database? Forms are used to
do this. In the language of databases, a form is a front end for data entry and editing.
Figure 209: Fields of a simple form
Figure 210: Simple form with additions
A simple form consists of the fields from a table (Figure 209). More complex forms can contain
much more, including additional text, graphics, selection boxes, and many other elements. Figure
210 is made from the same table with a text label (Fuel Purchases), a list box placed in
PaymentType, and a graphic background.
A list box is useful when a field contains a fixed choice of options. It saves you from having to type
in data by hand, and ensures that invalid options are not entered.
In our database, payments for food or fuel might be made from one of two credit cards (Dan or
Kevin) or in cash, so these would be the available options for all boxes that contain payments.
To create a list box, we first need to create a small, separate table containing the options. This is
then linked to the corresponding field in the form. The topic is dealt with in detail in the Base User
Guide and will not be pursued further here.
Using the Wizard to create a form
We will use the Form Wizard to create a Vacations form, which will contain a form and a subform
In the main database window (Figure 199), click the Forms icon in the left column. In the Tasks list,
double-click Use Wizard to Create Form to open the Form Wizard (Figure 211). Simple forms
require only some of these steps, while more complex forms may use all of them.
Step 1: Select fields.
1) Under Tables or queries, select Table: Vacations. Available fields lists the fields for the
Vacations table.
2) Click the right double arrow to move all of these fields to the Fields in the form list. Click
Next.
Chapter 8 Getting Started with Base | 227