Using the NorthWind database:

1. Find the employees that have created no purchases (using a set operation)
2. Find the employees that have created no purchases (not using a set operation)
3. Find the shippers that have handled an order shipped to the state of NY or to state of CO (using a set operation)
4. Find the shippers that have handled an order shipped to the state of NY or to state of CO (not using a set operation)
5. Compute the total number of items (quantity) to be shipped to the state of NY.
6. Compute the cities that have a customer and are the destination of a shipment.
7. Compute the cities that have a customer or are the destination of a shipment.