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HI, i use models User and Groups connected with many to many association, so i have users table, groups and groups_users. lets say i create one user and one group. next i add a group to user. so now my table groups_users has one entry i.e. group_id | user_id _________|________ 1 | 1 ok, when i delete both my group and user, above entry is not deleted, thus leaving alone without