When you have a database normalized to 3NF (Third normal form) and you need to take it from paper or any other format to a file maker pro, you must make an ER diagram. This simply involves matching primary keys to foreign keys.

1. Start in a table that has no foreign keys and choose a primary key from there.

2. Find the table with the related foreign key attribute.

3. Work out the cardinality of the relationship e.g. 1-Many or 1-1 but never Many-Many.

4. Draw a box with the entity name in and join it to another containing the foreign key.

5. To mark the cardinality on the one side one ‘leg’ and on the many side three ’legs’. Remember it is not
always a square shape the boxes make.

6. When creating a database in file maker pro it is advisable that you have beside you your ER Diagram for
reference.

7. Enter all the attribute name and table names in to the correct tab in the box that pops when creating a
new database.

8. As drawing the ER Diagram match primary key to the related foreign key attribute by dragging the
relationship legs between the tables (it probably will not look like.

9. This ensure that Referential integrity (Scot’s rule) is enforced creating a solid database structure.

If you were to read a 1-Many relationship backwards it would read 1-1 not Many-1. In 3NF we have eliminated the possibility of having a Many to Many relationship.

Any comments and/or corrections welcome.

For further help go to www.jhigh.co.uk/dbases/

By Neil Gillespie