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Figure 185: View of some fields from the Vacations table

A View is also a table. Its fields come from the fields of one or more

tables of the database. It provides a way to look at a number of fields

without regard to the table to which any of the fields belong. A View

can consists of some of the fields of one table as in Figure 185. Or, it

can consist of fields from more than one field as in Figure 186.

Figure 186: View of fields from the Fuel and Payment Type tables

Caution

Data can not be entered into a View like it can be added to a

table. It is strictly for viewing data which has already been

entered into the table.

Defining relationships

Now that the tables have been created, what are the relationships

between our tables? This is the time to define them based upon the

questions we asked and answered in the beginning.

When on vacation, we want to enter all of our expenses all at one time

each day. Most of these expenses are in the Vacations table, but the

fuel we buy is not. So, we will relate these two tables using the Date

fields. Since the Fuel table may have more than one entry per date,

this relationship between the Vacations and Fuel tables is one to many.

(It is designated 1:n.)

The Vacations tables also contains several fields for the type of

payment used. For each field listing the payment type, there is only

one entry from the Payment Type table. This is a one to one

relationship: one field in one table to one entry from the other table. (It

is designated 1:1.) Other tables also contain fields for the type of

payment. The relationship between these fields of those tables and the

Payment Type table are also 1:1.

Since the Payment Type table only provides a static list, we will not be

defining a relationship between the Payment Type table and the fields

Chapter 8 Getting Started with Base 253

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OpenOffice.org OpenOffice - 3.0 Quick Start Guide Page 253