Which design better when use foreign key instead of a string to store a list of id

Posted by Kien Thanh on Programmers See other posts from Programmers or by Kien Thanh
Published on 2012-11-16T11:14:24Z Indexed on 2012/11/16 17:16 UTC
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database

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database-design

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data-structures

I'm building online examination system. I have designed to table, Question and GeneralExam. The table GeneralExam contains info about the exam like name, description, duration,...

Now I would like to design table GeneralQuestion, it will contain the ids of questions belongs to a general exam.

Currently, I have two ideas to design GeneralQuestion table:

It will have two columns: general_exam_id, question_id.
It will have two columns: general_exam_id,
list_question_ids (string/text).

I would like to know which designing is better, or pros and cons of each designing.

I'm using Postgresql database.

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