mysql - How should I structure my table and foreign keys? -


i noob when comes foreign keys please point me good/descriptive learning resources may helpful. let's trying build basic user/role system. have 2 tables:

user_role : id, role user: id, role_id, name

how , type of foreign key constraint should use in both tables? want role assigned 1 user cannot deleted till user moved role.

i using phpmyadmin, if can give directions it, appreciated.

a simple query adding foreign key constraint user table follows:

alter table `user`  add constraint fk_user_role  foreign key (`role_id`)  references `user_role` (`id`)

that accomplish setting out do.


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