sql - Incorrect data when run as subquery -

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i have query takes data given media table joins user table :

select media.id, media.user_id,@rownum := @rownum + 1 position  inner join users on media.user_id = users.id media_table  order media.distance asc, media.media_likes_count desc, media.media_views_count desc;

this query produces nice looking table follows:

media_id, user_id, position 39199   , 3949   , 1 39299   , 3149  , 2 39359   , 3944   , 3 39369   , 3349   , 4 39379   , 3149   , 5 39389   , 3449   , 6

from derived table, want position of media_id = 39389.

however if include query in subquery this:

select position (select media.id, media.user_id,@rownum := @rownum + 1 position  inner join users on media.user_id = users.id media_table  order media.distance asc, media.media_likes_count desc, media.media_views_count desc;) media_id = 39389

then columns 'shuffle' , 39389 not have position 6 anymore.

not withstanding errors in query, assuming typos, perhaps you're issue not initializing user defined variable. condensed version works me:

select postition (   select yourresults.*, @rn:=@rn+1 postition   yourresults      join (select @rn:= 0) t   order media_id   ) t media_id = 39389

while not work: 

select postition (   select yourresults.*, @rn:=@rn+1 postition   yourresults    order media_id   ) t media_id = 39389

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