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Overview
On this lesson, we are going to review one of the features related to database that visualize two important topics: major entities within the system and the relationship among these entities. Entity Relationship Diagram (ERD) is a type of structural diagram that we can use in database design.
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Let’s check how we can use the ERD in Wayfast!
How to create Entity Relationship Diagrams?
First we need to navigate through the “Database” tab at the top header. Then click on “ERD” section
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This section will display all the diagrams associated to the project. Let’s click on “New ERD” button to create a new diagram.
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NOTE: Keep in mind that we need to establish an active requirement on the project to create a new diagram. Otherwise, we can only view the existing ERDs in read only mode. |
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A new tab is opened on the browser, we need to initially input the name of the new diagram and click on “Ok” button.
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In our example, we have “HWD_Roles” available from the “Dataset” lesson in the project.
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NOTE: We need to synchronize the model object from database in Wayfast to view all the updated existing tables. Otherwise, those recently created tables won’t be available to make the diagram. |
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All the attributes from the table allocated in the database are populated in the example without creating the new columns. If we create a new column using an existing name, the application won’t be able to save the attribute.
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Click on “Save” button before continue working on the diagram.
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Also we can remove the entire diagram or view it again to modify any relationship in the model.
Recap
In the first part, we learnt more about the entity relationship diagrams (ERD) and how they are helpful to build our database model. Then we review the ERD tool available in Wayfast to create the entities in the diagram and make the inter-relationships between all of them.