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Does updating grades extend a feature that shows grades? I am not sure if the notation is correct, so I am hoping you guys will know it.

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Does updating grades extend a feature that shows grades? I am not sure if the notation is correct, so I am hoping you guys will know it.

No, it does not extend. Updating grades is a standard CRUD operation.

You may think of extension use cases as an Interface with the behaviors of the context that it presents. Programming to the interface reduces dependency on implementation specifics and makes code more reusable and flexible to changes.

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In UML modeling, you can use an extend relationship to specify that one use case (extension) extends the behavior of another use case (base).

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Suppose we sell products. Customers can set requirements to a degree like setting size or color. So, such requirements add extra flow to the use case. In such scenarios, extend relationship can be used to pull the alternative flows into a new use case.

Does updating grades extend a feature that shows grades? I am not sure if the notation is correct, so I am hoping you guys will know it.

Updating grades do not extend show grades.

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So, "Show grades" and "Update grades" shouldnt be in a relationship? –  Kajzer Oct 13 '12 at 13:50
    
"Update grades" <<include>> "Show grades" is a possibility, if after "Update grades" "Show grades" is required. –  Shuvo Oct 13 '12 at 14:37
    
This is not correct. To state that one use case extends another use case you use inheritance. –  vainolo Oct 14 '12 at 9:33
    
Sorry but my previous comment is not correct (and I don't seem to be able to delete/edit it). To quote from the UML Superstructure: "A relationship from an extending use case to an extended use case that specifies how and when the behavior defined in the extending use case can be inserted into the behavior defined in the extended use case". So this is the correct way to do it. And again, sorry for my previous answer. –  vainolo Oct 14 '12 at 9:55
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