mySql query - web file sharing program - mysql

Question

Here is my code. It is supposed to select the name of the person "to_whom" I'm sharing a particular file,
and the whole thing needs to return back the user_id (u_c.to_whom) and the user_name,
so I can populate my friends list with a checkboxe next to each other, that once clicked,
will share (save into a DB table) that particular file to a specific person.
This is from a web-app where users share files among each other.
SELECT u_c.to_whom, u.user_name
FROM files f
LEFT JOIN users_connections u_c
ON (u_c.who = :user_id OR u_c.to_whom = :user_id) AND u_c.friends = "Y"
LEFT JOIN users u
ON u.user_id = u_c.to_whom
WHERE f.file_id = 90
In the table files we have
file_id, file_name, file_desc, etc...
In the table users connections
id, who, to_whom, friends
1 1 4 Y
meaning that user 1 had initiated a friendship to user 4 and "Y" means the friendship is TRUE (N = still pending)
And in users we have
user_id, user_name
1 Jack
I cannot seem to get this working for some reason.
Can any advanced user help me out?
Thanks a bunch!!

Answer 1

I found the answer to this code. It is an essential code if you want to build a sharing file system.
$query_list_count = "SELECT COUNT(user_id)
FROM users_connections u_c
LEFT JOIN users u
ON u.user_id = u_c.who OR u.user_id = u_c.to_whom
LEFT JOIN files f
ON f.file_id = :file_id
WHERE (u_c.who = :user_id OR u_c.to_whom = :user_id AND friends = :friends)
GROUP BY u.user_id
";
$result_list_count = $db->prepare($query_list_count);
$result_list_count->bindValue(':user_id', $_SESSION['user_id'], PDO::PARAM_INT);
$result_list_count->bindValue(':friends', "Y", PDO::PARAM_STR);
$result_list_count->bindValue(':file_id', $file_id, PDO::PARAM_INT);
$count_ = $result_list_count->fetchColumn();