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The crewmember deletes a graph on the webpage. the front-end does a call to the back-end. The resource is only responsible for returning the response so it gets delegated to GraphResource. The GraphService delegates this to the GraphDAO because getting the data from the database is not the responsibility of the controller. In the GraphDAO the graph gets deleted from the database. The benefit of this structure is that you can easily swap the classes which results in low cohesion and high coupling. This structure is based of the the layer pattern.
Tab CRUD
Delete Tab
Database Design
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