mysql - Friends my Friends recently add -

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im building platform users can connect other users (social platform)

i have table called friends , saving connections 

user_id  |   friend_id  |   request   |   add_date

now need write sql query recent friends specific user's friends added or not friends of user. user must accepted.

think of news feed , see friends added (the new add person can friend or not)

so far have works when friend added people have. 

select user_main_id frmname, friend_id type_id, add_date date friends  friend_id  in  (select friend_id  friends (friend_id='$user_id' or user_main_id='$user_id')  , request=1 , friend_id!=$user_id)  , request=1 , friend_id!=$user_id , user_main_id!=$user_id order date desc

maybe there better why approach this.

suggestions? appreciated thanks. connection bilateral, no difference between user_id , friend_id. designed names , had carried forward.

sample record

96618   50683   1   2013-05-08 13:44:31 96618   1230    1   2013-04-03 18:28:51 11671   96618   1   2013-04-03 13:26:51 11671   1230    1   2013-03-23 18:26:08

once 96618 connects 50683 happens. users 11671 example msg saying friend 96618 friends 50683

try this:

select f2.friend_id friends f1                         # friends of target user     inner join friends f2         on f1.friend_id = f2.user_id     # friends of friends        , f2.request = 1         , f2.friend_id != f1.user_id     inner join friends f3               # limiting mutual friends     on f2.friend_id = f3.user_id , f3.friend_id = f1.user_id f1.user_id = 11671 , f1.request = 1 order f2.add_date desc

please note current table structure, going need 2 rows each friendship, 1 each direction. 1 row, want split 2 tables - friendships , friendship_members.


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