Tables design question

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От JORGE MALDONADO
Тема Tables design question
Дата
Msg-id CAAY=A7-BnHPUH09k_JA68zSTNeKCuqJmfJY3vj5j0c-7c=1-HA@mail.gmail.com
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Ответы Re: Tables design question  ("David G. Johnston" <david.g.johnston@gmail.com>)
Список pgsql-novice
I have the following tables:
* courses
* prerequisites
* corequisites

The table "courses" has general data about school courses.
The table "prerequisites" has data about courses that must already have been taken for a certain course.
The table "corequisites" has data about courses that must be taken at the same time that another course.

This means that a course might have zero or more "prerequisites" and zero or more "corequisites" and both point to "courses".

The image below show what I think should be done.
I will very much appreciate any feedback about my approach.




Best regards,
Jorge Maldonado
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