A query is a request for data from one or more tables. When you execute a query, rows that satisfy the query condition are returned as a table. Similarly, when a query embedded in another query or a program gets executed, the data retrieved is returned as a table to the other query or program.
In this chapter you learn how to write basic queries using the SELECT statement. Once you master the basic queries, you can start learning about queries within other queries in Chapter 6, �Subqueries� and within PL/SQL programs in Chapter 10, �PL/SQL.�
All queries regardless of their complexity use the SELECT statement. The SELECT statement has the following general syntax.