3.7. Analyzing and Manipulating Data

With MySQL you can not only retrieve raw data, but also analyze and format the data retrieved. For instance, suppose we want to know how many titles we stock by Leo Tolstoy. We could enter a SELECT statement containing a COUNT⁠(⁠ ⁠ ⁠) function like this:

SELECT COUNT(*)
FROM books
JOIN authors USING(author_id)
WHERE author_last = 'Tolstoy';
   
+----------+
| COUNT(*) |
+----------+
|       12 |
+----------+