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Entity Relation Diagrams
Visio provides a powerful ERD capability
1 Open visio and choose Database > Database Model Diagram
By default visio uses an arrow to represent relationships. It is more usual to use the crows feet notation to show cardinality. To set this up you need to change one of the Database Options.
2 From the menu bar choose Database > Options > Document then choose the Relationship tab and
- check the crows feet check box.
- Check Show verb phrase radio button (check both forward and reverse checkboxes)
From a teaching perspective when you are learning ERDs I prefer to join the primary keys to the foreign keys. Visio connects the entities (as it should) but the actual likes to not connect the relevant keys) .. so I have created a basic stencil (below) that allows you to create basic ERD's and as the lines are created as objects can be positioned anywhere on the page. This will allow you to manually connect lines to the appropriate keys.
An example ERD not showing the attributes(created using the stencil) follows:
To install the stencil in Visio 2007. File> Shapes> Open Stencil