sql question 1

[megabyte214]

Below is a query and it is not displaying the count for authors who do not have any books. I understand why, but I do not know how to fix it. I need it to return 0 for authors with no books.

select lastname, count(ba.isbn) from author as a, bookauthor as ba, book as b where b.isbn = ba.isbn and ba.authorid = a.authorid group by a.lastname asc;

Thanks in advance.

 

[swampBoogie]

select a.lastname, count(ba.isbn) 
from author as a left join  bookauthor as ba
on ba.authorid = a.authorid
group by a.lastname

I don't see why you need to join the book table. Also, using asc or desc on group by is not standard.