In the last chapter, we surveyed the different SQL statements that are available and learned the essentials that we need to create, maintain, and use a database. In this chapter, we will concentrate in detail on the most versatile SQL statement, the SELECT statement. We'll learn how to use SELECT statements to:
Put data in order
Combine data from different tables
Use as subqueries
The first three topics are elaborations on the SELECT statement as we already know it. We'll learn a few new clauses for grouping and ordering data. We'll also learn a few new options for the FROM and WHERE clauses that allow us to combine data from multiple tables.
The next topic, subqueries, ...