Oracle SQL and PL/SQL Handbook: A Guide for Data Administrators, Developers, and Business Analysts

Practice

1:	Use the UNION operator to identify the employees who are named JOHN, HAROLD, and WILLIAM.
2:	Identify the employees who have purchased tools but not eyeglasses.
3:	Identify the employees who were born before and after 1920. For the employees who were born before, use the text literal Born Before 1920. For those born after, use Born After 1920.
4:	Modify your query from question 3 to list only the employees born before 1920 who have purchased tools and those born after 1920 who have purchased eyeglasses.
5:	Use a correlated subquery to determine the departments that do not have employees.
6:	Create a SELECT statement that can produce a list of tool purchases for an inputted department.
7:	Create a SELECT statement that can produce a list ...