Chapter 7. SELECT Statement: The FROM Clause
Introduction
The processing of a table expression begins at the FROM
clause. In fact, this is the starting point of processing a table expression, which is why this clause is discussed in detail first.
In this chapter, we describe the basic features of the FROM
clause. In previous chapters, you saw many examples of this clause. The FROM
clause is an important clause because each table from which we “use” columns in the other clauses should be specified here. By “using,” we mean, for example, that a column appears in a condition or in the SELECT
clause. Simply, in the FROM
clause, we specify the tables from which the result of a table expression will be retrieved.
The FROM
clause has many different forms. ...
Get Introduction to SQL: Mastering the Relational Database Language, Fourth Edition/20th Anniversary Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.