Yurttas/PL/DBL/mysql-f-2010/01/PC/q17.sql

 1/*
 2REM
 3REM q17.sql
 4REM
 5REM Find the manufacturers of PC's with at least
 6REM three different speeds.
 7REM
 8*/
 9
10\. set-db.sql
11
12SELECT P.maker
13FROM Product P, PC
14WHERE P.model=PC.model
15GROUP BY P.maker
16HAVING COUNT(DISTINCT speed)>=3;