Klausa GROUP BY dengan alias?

DIPERBARUI2

1. Sepertinya Anda tidak perlu menyertakan TotalSales di GROUP BY. Melihat permintaan Anda, itu tidak masuk akal. Buang saja dari pilihan dalam.

2. Untuk memasukkan buku yang belum terjual harus menggunakan outer join

Meskipun demikian, kueri Anda mungkin terlihat seperti

SELECT COALESCE(author_id, 'All Authors') author_id
     , COALESCE(book_id, IF(author_id IS NULL, 'All Books', 'Subtotal')) book_id
     , COALESCE(total_quantity, 'No books') total_quantity
     , COALESCE(total_sales, 'No Sales') total_sales   
 FROM 
(    
 SELECT author_id 
      , b.book_id 
      , SUM(quantity) total_quantity  
      , SUM(quantity * order_price) total_sales   
   FROM book_authors b LEFT JOIN order_details d
     ON b.book_id = d.book_id
  WHERE author_sequence = 1           
  GROUP BY Author_id, Book_ID WITH ROLLUP  -- you don't need TotalSales here
) q;

Contoh keluaran:

+-------------+-----------+----------------+-------------+
| author_id   | book_id   | total_quantity | total_sales |
+-------------+-----------+----------------+-------------+
| 1           | 1         | 12             | 278.50      |
| 1           | 3         | No books       | No Sales    |
| 1           | Subtotal  | 12             | 278.50      |
| 3           | 2         | 5              | 75.75       |
| 3           | Subtotal  | 5              | 75.75       |
| All Authors | All Books | 17             | 354.25      |
+-------------+-----------+----------------+-------------+

Ini SQLFiddle demo