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SQL Joins

1. Login in to the mysql client using the login name and password provided by your instructor (if not already logged in). 2. View the existing databases that the MySQL Server is maintaining. SHOW DATABASES; 3. Utilize the photo_album database. USE photo_album; ---- If Need be, recreate the database and load the SQL data in that will be used for this lab CREATE DATABASE photo_album; SOURCE /tmp/photo_album.sql; 4. Query the database to display the active primary customer (email, first and last name) and all the associated active login names associated with that customer. SELECT customers.email_customer, customers.fname, customers.lname, logins.login_name  FROM customers, logins WHERE customers.email_customer = logins.email_customer  AND customers.active_customer = 'True'  AND logins.active_login = 'True';

Right Outer Join

A right join is another type of outer join, written using the RIGHT JOIN keywords. Every RIGHT JOIN corresponds to an equivalent LEFT JOIN. The only difference is that the roles of the tables are reversed relative to the roles in a RIGHT JOIN. That is, the right table is the reference table, so a RIGHT JOIN produces a result for each row in the right table, whether or not it has any match in the left table. The previous example showed the result of a LEFT JOIN . The example below is the same statement, but with a RIGHT JOIN: mysql> SELECT Name, Language -> FROM Country -> RIGHT JOIN CountryLanguage -> ON Code = CountryCode -> WHERE CountryCode IS NULL; Empty set (#.## sec) Note that the join is now being referenced to the right table CountryLanguage, which yields no results (empty set). Syntactically, converting a left join to a right join requires only that the order be reversed in which the tables are named. It isn't necessary to also reverse the