Relational database design:two 1 to many relations -

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i have table users (id,name) , operations (id,date,id_user,id_target_user)

if didn't have id_target_user column i'll make on relation users.id operations.id_user (every user can have multiple several operations) problem operation maybe related user

how solve this? can't create 2 relations on same key can i?

yes can.

  • id_user foreign key users.id.

  • id_target_user foreign key users.id.

that's need.


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