Procedure within the merge

My scenario

MERGE Books
USING
 (
 SELECT
  MAX(BookId) BookId,
  Title,
  MAX(Author) Author,
  MAX(ISBN) ISBN,
  MAX(Pages) Pages
 FROM Books
 GROUP BY Title
 ) MergeData ON Books.BookId = MergeData.BookId
 WHEN MATCHED THEN
  UPDATE SET
   Books.Title = MergeData.Title,
   Books.Author = MergeData.Author,
   Books.ISBN = MergeData.ISBN,
   Books.Pages = MergeData.Pages
 WHEN NOT MATCHED BY SOURCE THEN DELETE;
GO
SELECT * FROM Books

MERGE Books
USING
 (
  exec Proc Procname
  ) MergeData ON Books.BookId = MergeData.BookId
 WHEN MATCHED THEN
  UPDATE SET
   Books.Title = MergeData.Title,
   Books.Author = MergeData.Author,
   Books.ISBN = MergeData.ISBN,
   Books.Pages = MergeData.Pages
 WHEN NOT MATCHED BY SOURCE THEN DELETE;
GO
SELECT * FROM Books

Thiru