How to count the number of 02 tables

How to count the number of 02 tables - Printable Version

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How to count the number of 02 tables - garidinh - 07-09-2016

Hi every body ?
I have 2 table data:
db_category:

+idcate
+name
db_book:
+ idbook
+ name
+ idcate

Now I want to count the number by category.

Example:
Book 1: 2 file
Book 2: 5 file

Please help me, thanks Big Grin

RE: How to count the number of 02 tables - Paradinight - 07-10-2016

This makes no sense at all. Huh

example

Code:
SELECT 

    category.name, 

    count(book.id)

FROM

    category

INNER JOIN

    book

ON category.id = book.id

GROUP BY category.id

cat_a 12
cat_b 10