I have two tables. One of them (user_profile table) has a field named "user_profile_id" and the other one (user_friend table) has two fields named "user_profile1_id" and "user_profile2_id" which are FK to the first table.
I want to check if there are any users in user_profile which are not in user_friend table, neither in user_profile1_id, nor user_profile2_id.
What query should I use?
CREATE TABLE user_profile ( --fields ) CREATE TABLE user_friend ( user_profile1_id INT, user_profile2_id INT )