Exercises
Product ( pname, price, category, maker)
Purchase (buyer, seller, store, product)
Company (cname, stock price, country)
Person( per-name, phone number, city)
Ex #1: Find people who bought telephony products.
Ex #2: Find names of people who bought American products
Ex #3: Find names of people who bought American products and did
Ex #4: Find names of people who bought American products and they
Ex #5: Find people who bought stuff from Joe or bought products
from a company whose stock prices is more than $50.