Database Schema - MYSQL and PHP

Question

I am a newbie with creating a robust database system. But after completing, my challenge lies with two table, User table and Category table . Each user in the database must create categories for their products. Initially, i made it a many to many relation (creating a pivot table user_category table ) but now, i having doubts.

Can i still use the many to many relationship for the user and category table?

Answer 1

If 2 or more users can have the same categories I would recommend to use this structure:

user table:
|user_id|user_name|...

categories table:
|category_id|category_name|...

user_categories table:
|user_id|category_id|

If a category is unique per user I would add the user_id column in the category table

user table:
|user_id|user_name|...

categories table:
|category_id|category_name|user_id|...