É apenas uma consulta simples envolvendo um
JOIN
:SELECT users.uid, users.uname, COUNT(logs.logid) AS logins
FROM users
LEFT JOIN logs ON logs.uid=users.uid
GROUP BY users.uid
ORDER BY logins DESC
JOIN
:SELECT users.uid, users.uname, COUNT(logs.logid) AS logins
FROM users
LEFT JOIN logs ON logs.uid=users.uid
GROUP BY users.uid
ORDER BY logins DESC