Question

I have the following query but it’s returning multiple entries from the profile_photos table. Is it possible to return just one random entry from the profile photos table? If not random is it possible to limit the number of results to 1?

Here is my current query:

$sql = "SELECT * FROM login_users " .
       "LEFT JOIN profile_photos ON profile_photos.user_id = login_users.user_id " .
       "LEFT JOIN profiles ON profiles.user_id = login_users.user_id " .
       "WHERE login_users.restricted <> 1 " .
       "ORDER BY login_users.birthdate DESC " .
       "LIMIT 0, 20";

Answer 1

Here is one method. Look up a random photo and then join in the additional information:

SELECT *
FROM (select lu.*,
             (select photo_id
              from profile_photos
              where lu.user_id = profile_photos.user_id
              order by RAND()
              limit 1
             ) as photo_id
      from login_users lu
     ) lu LEFT JOIN
     profile_photos pp
     ON pp.photo_id = lu.photo_id LEFT JOIN
     profiles p
     ON p.user_id = lu.user_id 
WHERE lu.restricted <> 1
ORDER BY lu.birthdate DESC
LIMIT 0, 20

This assumes that photo_id is the primary key on profile_photos.