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  1. #1
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    Database Design review please!

    Hello, I am new to both the DBForum community and to Databases themselves. I am taking a relational database course online (dumb idea) and seem to be struggling with some of the concepts. I was wondering if someone could look it over and see if it makes any sense? thanks a ton!
    Last edited by georgebluff; 10-25-10 at 07:47.

  2. #2
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    Quote Originally Posted by georgebluff View Post
    ... and seem to be struggling with some of the concepts.
    which ones?
    rudy.ca | @rudydotca
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  3. #3
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    Most of it seems confusing, but in particular Foreign Keys. If you look at the ERD I post, my section part seems to have multiple Foreign Keys. Should the Faculty_Id a foreign key, or should it just be part of the section? When you looked at my ERD, did everything seem to be correctly related?

  4. #4
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    Quote Originally Posted by georgebluff View Post
    When you looked at my ERD, did everything seem to be correctly related?
    that's pretty hard to say without any information from you

    an entity-relationship diagram is "correct" only insofar as it properly reflects the actual (or desired) characteristics of the data you are modelling
    rudy.ca | @rudydotca
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  5. #5
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    The ERD that I created is modeling a database for a student registering for courses offered by a college or university. I am not sure if I'm suppose to start creating relationships around the Student_Id, or other entities that exist in the process of registering for a courses.

  6. #6
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    do you know how to distinguish between an entity and an attribute of an entity?
    rudy.ca | @rudydotca
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  7. #7
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    I thought an entity refers to an item that can be tracked and described in the database, and the attribute was information describing the entity. As for example in my ERD, the attributes of the Faculty were LName, FName, ect...,
    but in Section, I thought that to have the Faculty related to the Section, I could just call the primary key Faculty_Id as an foreign key to the section, so that it would list if Faculty_Id within the Section entity.

    Am I way off?

    p.s. thank you for you quick responses. I wasn't even expecting anyone to respond at all...

  8. #8
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    Quote Originally Posted by georgebluff View Post
    I thought an entity refers to an item that can be tracked and described in the database, and the attribute was information describing the entity.
    that's a pretty good description

    i don't understand what you said about faculty and section, though

    what's a section? what's a faculty?

    if you could give a definition of each of these entities, it would be easier for me to see how they are related
    rudy.ca | @rudydotca
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  9. #9
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    The faculty is a teacher.

    The Section is one section of a course being offered.

    So I thought the correct relationship is one faculty teaches multiple courses. One course offers multiple sections, having one teacher teach the final one section of a specific course.

    Then there are multiple departments offered through the registrar, and multiple students can register for a course through one registrar. Then after the registrar processes a registration request, the registrar creates multiple class schedules unique to each student_id.

  10. #10
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    Quote Originally Posted by georgebluff View Post
    So I thought the correct relationship is one faculty teaches multiple courses. One course offers multiple sections, having one teacher teach the final one section of a specific course.
    if this is the way it is, then that's how i'd model it

    the only tricky part would be whether you want a relationship from the teacher to the course, and i would think not, because it would be obtained transitively from the relationship between teacher and section

    Quote Originally Posted by georgebluff View Post
    Then there are multiple departments offered through the registrar, and multiple students can register for a course through one registrar. Then after the registrar processes a registration request, the registrar creates multiple class schedules unique to each student_id.
    sounds right

    any more questions about the concepts?
    rudy.ca | @rudydotca
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  11. #11
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    In regards to the Request entity, is the Registration_Request correctly placed?

    What I was trying to do is Multiple students create a registration_request unique to their student Id. Then the Registrar takes the Registration_request and compiles a StudentScedule, which would be unique to both the Student_ID, and the Registration_Request created by the student.

    Again, thank you for looking this over and helping me out. I have been working on this for about two weeks now, but since I'm taking this class online I don't have the reassurance of showing my teacher what I'm trying to do, and get some input on it.

  12. #12
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    Quote Originally Posted by georgebluff View Post
    In regards to the Request entity, is the Registration_Request correctly placed?
    what doubts do you have about it?
    rudy.ca | @rudydotca
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