Join (SQL)
A SQL Join clause is a way to retrieve information from two or more tables in a database.  When a database programmer wants to do a join command, they will type about the databases they want to get information from, and the type of join they want to use.  There are five types of joins.  A normal JOIN, which is also called an INNER JOIN, a LEFT OUTER JOIN,  aRIGHT OUTER JOIN,  aFULL OUTER JOIN and CROSS JOIN.