Welcome to our free Advanced Oracle SQL Queries tutorial. This tutorial is based on Webucator's Advanced Oracle SQL Queries course.
Oracle SQL queries are not limited to selecting data from a single table. Several tables can be accessed within a query and the data aggregated into a single result set which is returned to the user. The relationship between two tables is known as a join and consists of a mapping of values between specified columns in each table. In this chapter you will learn about various types of joins and their application to data retrieval.