This code give me the next error:
DB Error: Bad SQL Query: SELECT user_t_images, user_name, user_id, SUM(image_hits) AS sum FROM 5images_users, 5images_images WHERE user_level >= '2' ORDER BY user_t_images DESC LIMIT 10
Column 'user_id' in field list is ambiguous
$sql = "SELECT user_t_images, user_name, user_id, SUM(image_hits) AS sum FROM ".USERS_TABLE.", ".IMAGES_TABLE."
WHERE user_level >= '".USER."'
ORDER BY user_t_images DESC
LIMIT 10";
Help me please