mysql - Join returning zero elements where it should not -


the below sql statement looks friendship between 2 user elements, querying friendship table using users' profile_id#s, line added working statement left outer join block_user_filters blockedusers on blockedusers.profile_id_1 = 'abcde2' want see if user abcde2 has blocked anyone, , if want filter these friendships tableon clause left outer join block_user_filters blockedusers on blockedusers.profile_id_1 = 'abcde2' have block table populated block row of user abcde2 friended user element, whole statement returning 0 rows. please me fix if can. thank you

select     users1.username firstusername,    users2.username secondusername,   users1.profile_id firstprofid,   users2.profile_id secondprofid,   users1.picup firstpicup,    users2.picup secondpicup  `users`    left outer join  `friendship`          on friendship.profile_id_1 = users.profile_id or friendship.profile_id_2 = users.profile_id   left outer join users users1 on users1.profile_id = friendship.profile_id_1   left outer join users users2 on users2.profile_id = friendship.profile_id_2   left outer join block_user_filters blockedusers on blockedusers.profile_id_1 = 'abcde2'   users.profile_id = 'abcde2' , blockedusers.profile_id_1 != 'abcde2' , friendship.state = 1 limit 6

edit: answer , comments, unfortunately after trying null, it's still returns 0 rows, thinking should checking blockedusers.profile_id_2 instead , separate 2 possibilities of friendship table's first user existance (in either friendship.profid_1 or _2), , combine them union, has weirder results, need head together... 

select users1.username firstusername, users.username secondusername,  users1.profile_id firstprofid, users.profile_id secondprofid, users1.picup firstpicup, users.picup secondpicup  `users`  left outer join  `friendship` on friendship.profile_id_2 = users.profile_id left outer join users users1 on users1.profile_id = friendship.profile_id_1 left outer join block_user_filters blockedusers on blockedusers.profile_id_1 = 'abcde2' users.profile_id = 'abcde2' , blockedusers.profile_id_2 != friendship.profile_id_1 , friendship.state = 1 union select users.username firstusername, users.username secondusername,  users.profile_id firstprofid, users2.profile_id secondprofid, users.picup firstpicup, users2.picup secondpicup  `users`  left outer join  `friendship` on friendship.profile_id_1 = users.profile_id left outer join users users2 on users2.profile_id = friendship.profile_id_2 left outer join block_user_filters blockedusers on blockedusers.profile_id_1 = 'abcde2' users.profile_id = 'abcde2' , blockedusers.profile_id_2 != friendship.profile_id_2 , friendship.state = 1

i think looking for. last line of last join should match on second id in friendship. if there match, omitted blockedusers.profile_id_1 null criteria in clause.

select users1.username   firstusername,         users2.username   secondusername,         users1.profile_id firstprofid,         users2.profile_id secondprofid,         users1.picup      firstpicup,         users2.picup      secondpicup     friendship          left outer join users users1                      on users1.profile_id = friendship.profile_id_1         left outer join users users2                      on users2.profile_id = friendship.profile_id_2         left outer join block_user_filters blockedusers                      on  blockedusers.profile_id_1 = 'abcde2'                     , blockedusers.profile_id_2 in (users1.profile_id, users2.profile_id)   (friendship.profile_id_1 = 'abcde2' or friendship.profile_id_2 = 'abcde2')        , friendship.state = 1         , blockedusers.profile_id_1 null   limit  6

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