|
This is a visual representation
of the database structure. Tables, containing data fields
are linked to other tables by relationships which specify
how the link operates. For instance:
| 1 -
* |
one record in the left hand table links
to 0 or more in the right hand table |
| 1 -
1 |
one record in
the left hand table links to one only in the right
hand table |
| 1 -
1..* |
one record in
the left hand table links to 1 or more in the right
hand table |
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