Contents Index Compatibility with Adaptive Server Enterprise Sample database schema

ASA SQL User's Guide

Joins: Retrieving Data from Several Tables


About this chapter 

When you create a database, you normalize the data by placing information specific to different objects in different tables, rather than in one large table with many redundant entries.

A join operation recreates a larger table using the information from two or more tables (or views). Using different joins, you can construct a variety of these virtual tables, each suited to a particular task.

Before your start 

This chapter assumes some knowledge of queries and the syntax of the select statement. Information about queries appears in Queries: Selecting Data from a Table.


Sample database schema
How joins work
Joins overview
Explicit join conditions (the ON phrase)
Cross joins
Inner and outer joins
Specialized joins
Natural joins
Key joins

Contents Index Compatibility with Adaptive Server Enterprise Sample database schema