CREATE TABLE products (Manufacturer VARCHAR, name VARCHAR)
CREATE TABLE manufacturers (name VARCHAR, code VARCHAR)

Find the name of companies that do not make DVD drive.
SELECT name FROM manufacturers EXCEPT SELECT T2.name FROM products AS T1 JOIN manufacturers AS T2 ON T1.Manufacturer = T2.code WHERE T1.name = 'DVD drive'
SELECT "name" FROM "manufacturers" EXCEPT SELECT "T2"."name" FROM "products" AS "T1" JOIN "manufacturers" AS "T2" ON "T1"."Manufacturer" = "T2"."code" WHERE "T1"."name" = 'DVD drive'