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Thread: ERD model

  1. #1
    Join Date
    Jun 2011
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    ERD model

    Hi,
    I'm just a total newbie.
    I'm trying to create ERD for a DB. This is an example: is it better to create an entity ESTIMATOR with attributes last name, first name, title, etc, or is it better to make each of those attributes an attribute of a parent entity, say PROPOSAL? What will be cons & prons?
    Thanks

  2. #2
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    last time i checked, a proposal doesn't have first and last names
    rudy.ca | @rudydotca
    Buy my SitePoint book: Simply SQL

  3. #3
    Join Date
    Jun 2011
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    Thanks

    Maybe it was the wrong example, but what I meant was, in general, what advantage will be to create another entity with its own attributes instead of assigning those attributes to the parent entity?
    Thanks

  4. #4
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    in general, it depends on the entities

    sorry, but that's the best i can do with the given information
    rudy.ca | @rudydotca
    Buy my SitePoint book: Simply SQL

  5. #5
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    Jun 2011
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    Thanks. Maybe when I have some more concrete examples I'll come back with the question. On the other hand, the whole thing would require much lengthier explanation, including the type of business, the requirements, the business culture, etc., etc..

  6. #6
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    Quote Originally Posted by dbphile View Post
    Thanks. Maybe when I have some more concrete examples I'll come back with the question. On the other hand, the whole thing would require much lengthier explanation, including the type of business, the requirements, the business culture, etc., etc..
    true:-
    but it is your problem which you are are on here looking for a solution. if its to much trouble for you to provide sufficient information should you be surprised if its to much trouble for people to hazard a guess at what that solution might be.

    its sort of similar to asking how long is a piece of string?
    there are many many answers, most of which may be correct for a specific piece of string, but in the absence of more information about your piece of string you are not going to get a useful answer
    I'd rather be riding on the Tiger 800 or the Norton

  7. #7
    Join Date
    Jun 2011
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    9
    Thanks,
    I just think that forum is not best suited for lengthy and complex questions, and that's why I said that I will come back with the question once I have broken down the problem to a question suitable for a forum.

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