SELECT TOP 5 r.Id, r.Name, Count(c.RepositoryId)
FROM Repositories AS r
LEFT JOIN Commits AS c ON r.Id = c.RepositoryId
LEFT JOIN RepositoriesContributors AS rc ON r.Id = rc.RepositoryId
GROUP BY r.Id, r.Name
ORDER BY  Count(c.RepositoryId) DESC, r.Id, r.Name