Given that this exam is about testing your knowledge of those aspects of SQL that were discussed in the lectures, no operations that were not discussed may be used. For example, JOIN and any variation of JOIN may not be used.
Write SQL for the query – based on the SQL Chapter’s multiple-company database – “Find every company that produces no products.” This time you may have an SFW embedded in the outer SFW, and it must be embedded using either the EXISTS or NOT EXISTS operator, whichever makes the complete SFW simpler. (You may not use GROUP BY or HAVING anywhere in your answer.)