Designing
Your First Database: 3
Data Entry
Form
If you enter the wrong department code, or say, an incorrect phone
number, you will be prompted to re-enter the data. You can if
you wish, type in your own message in Validation text, in field
properties.
We
are now going to design our second table, which will contain personnel
information.
- Go
to the Table tab and then click New then Design View, and enter
the fields below:
- You
will notice that the field Emp_Number appears again in this
table. This is so that we can link up the two tables with a
common field. Your table should look like the one below:
- Enter
the data below into the table except for the Emp_Number field.
- Now
close the table and open Staff Departments in Datasheet View.
Highlight the Emp_Number field with all the data, and click
the Edit menu and select Copy. Then close the table and open
the Personnel table. Highlight the Emp_Number column and go
to the Edit menu and select Paste. The Emp_Number column will
be pasted into the table.
- So
that all data added in this table is only accepted when it is
linked to the main table, Staff Departments, we will need to
link the common table Emp_Number and enforce "referential integrity".
It's a bit of a mouthful, but what it basically means is that
you could not for example, in the Personnel Table, add a new
employee without first creating an Employee Number in the Staff
Departments table. To do this we need to go to the Tools menu
and select Relationships.
- When
the above box appears click on Emp_Number in either table, and
drag and drop the field into Emp_Number in the other table.
- When
the Relationships dialogue box comes up, make sure Enforce Referential
Integrity is ticked and then click the Create button.
-
You will see now that a link has been established between the
tables via Emp_Number.
- Print
out copies of the data in both your tables.
The
benefit of having data in an organised format - a database - is
that information of a specific nature can be extracted from it.
This is called a Query. On the following page we are going to
design our own from the given criteria.
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