mysql - ISQL For each author, list their number, last name, and number of books they written -

select a.author_num, a.author_last, count(w.book_code) book.book b, book.author a, book.wrote w (b.book_code=w.book_code , w.author_num=a.author_num) order a.author_last desc; 

i have 3 tables; book, author, , wrote. need find how many books author has written. need sub-query?

you can use group by

select a.author_num, a.author_last, count(w.book_code) book.book b, book.author a, book.wrote w (b.book_code=w.book_code , w.author_num=a.author_num) group a.author_num, a.author_last order a.author_last desc; 

although feel column names aren't quite correct