hi guys
I'm newbie in Psql and I'm trying to build one function in order to
count the products for each supplier. So i'm gonna put it quite simply
though this example
Please, consider a table called books with the following fields
bookid, title, price, idPublisher
and one another table called publisher
Idpublisher, name, city, Books
Being in that last field from Publisher, called book, I gotta have the
amount of published books for each publisher.
