Q&A for professional and enthusiast programmers
SELECT TOP 50 Posts.Id, b.NumberOfDuplicates FROM Posts INNER JOIN (SELECT Posts.Id, COUNT(PostLinks.RelatedPostId) AS NumberOfDuplicates FROM Posts, PostLinks WHERE Posts.Id = PostLinks.RelatedPostId AND PostLinks.LinkTypeId = 3 GROUP BY Posts.Id) AS b ON Posts.Id=b.Id ORDER BY b.NumberOfDuplicates DESC