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Enhanced Entity Relationship Modeling - Theoretical questions

user2169
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user2169 Published in April 24, 2018, 8:17 am

This question already has an answer here:

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Well i have some basic theoretical questions about EER modeling on MySql Workbench for a school project.

So There are like 6-7 entities as far as i can understand. It has to do with users split to teachers and students. Teachers can set one or many thesis (title, description, etc) and a TODO_list pointing to that thesis. Then one or many TODO_lists are assigned to a student. Also some basic "media like" interaction with likes, follows, friends, comments on posts, etc.

I really couldn't attend class this year and things are getting blurry.

So i need on someone to answer me these basic questions.

1) If u have 2 tables and the relationship between them is a 1:1 relationship you just link them together and the primary key of "table_2" goes as secondary key to "table_1" ?

2) if u have 2 tables and the relationship between them is a N:M relationship then you create a third table (pivot table i think is its name) that contains both primary keys of "table_1" and "table_2" ?

3) what happens to a 1:M relationship ?

Thank you in advance!

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