MySQL. How to write a query with a subquery?

Question

MySQL

There is a product table , in this table there are 3 fields: maker (manufacturer), model (product model) and type (product type).
I'm required to list manufacturers that make pc but don't make laptop .
This is the query I got:

SELECT DISTINCT maker FROM product
WHERE type LIKE "PC%" AND type <> (
SELECT DISTINCT maker FROM product
WHERE type LIKE "Laptop%");

The error is: ERROR 1242 (
21000): Subquery returns more than 1 row

Answer 1

SELECT `p1`.`maker`
  FROM `product` AS `p1`
  LEFT `product` AS `p2` ON `p2`.`maker` = `p1`.`maker`
    AND `p1`.`type` LIKE 'PC%' AND `p2`.`type` LIKE 'Laptop%'
  WHERE `p2`.`maker` IS NULL