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ER Diagram Help

Discussion in 'Database' started by tia97, Sep 15, 2012.

  1. tia97

    tia97 New Member

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    Hello Im a student and we were given a business rule to draw an ER diagram from.
    "Each employee here is required to work in a single department. Departments can have many computers, but each computer belongs to only one department. Each employee uses at most one computer, but each computer may be used by several employees.” HINT: There are three entity sets here. In your diagram, do not make two copies of any entity set. One entity set will be in two different relationships."

    I managed to get some of it (I believe) but the part Im struggling on is Each employee uses at most one computer, but each computer may be used by several employees I know part of it is incorrect but just cant piece it all together. Can anyone assist? We are not using the "crow's feet method"

    Please see my attachment. Any help would be greatly appreciated.
     

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  2. jeenarohan

    jeenarohan New Member

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    In your question Department, employee and computer are the three main entity. First shows the relation between department and employee. Then shows the relation between department and computer. This will shows the relation of computer and the department. Final draw the diagram for employee and computer through their respective department. Hence you can achieve the result
     

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