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  • เผยแพร่เมื่อ 15 ก.ค. 2020

ความคิดเห็น • 8

  • @user-kh9ee4oo7p
    @user-kh9ee4oo7p 5 หลายเดือนก่อน +1

    In my college they taught us that we have weak entities my question is Should I just not use it?
    Also Should I use surrogate key instead of composite primary key and why?

    • @DustinOrmond
      @DustinOrmond  5 หลายเดือนก่อน

      Yes, weak entities exist but they are such a small use case. I have slides that talk about them, but I do not have lecture videos. In fact, I choose not to focus on these because the time is better spent on other topics. You choose whether to use a surrogate or a composite. The surrogate is often easier, and I tend to use a surrogate in all cases where the composite is 3+ attributes.

    • @user-kh9ee4oo7p
      @user-kh9ee4oo7p 5 หลายเดือนก่อน

      @@DustinOrmond Thank you so much, actually I use Django and I can only use surrogate key and Could you please tell me where can I find these slides?

  • @DucDuni
    @DucDuni ปีที่แล้ว +1

    I think you missed ‘1 section is taught by 1 professor’?

    • @DustinOrmond
      @DustinOrmond  ปีที่แล้ว

      You are right, there should be a many-to-one relationship between section and professor!

  • @user-kh9ee4oo7p
    @user-kh9ee4oo7p 5 หลายเดือนก่อน

    excuse me sir, I tried to register on your website, it asked me for a netID I tried different things could you please provide me netID or how to do it?

    • @DustinOrmond
      @DustinOrmond  5 หลายเดือนก่อน

      Unfortunately, I only allow students access right now. In the future, I may open it up to the public.

    • @user-kh9ee4oo7p
      @user-kh9ee4oo7p 5 หลายเดือนก่อน

      @@DustinOrmond Oh alright and thank you so much for the courses