O'Reilly logo

Beginning Oracle SQL: for Oracle Database 12c, Third Edition by Melanie Caffrey, Inger Jørgensen, Tim Gorman, Lex De Haan

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

CHAPTER 9

image

Retrieval: Some Advanced Features

This is the fourth chapter in a series about retrieval features of SQL. It is a logical continuation of Chapters 4, 5, and 8.

First, in Section 9.1, we revisit subqueries, beginning with an introduction to the three operators ANY, ALL, and EXISTS. These operators allow you to create a special relationship between main queries and subqueries, as opposed to using the IN operator or standard comparison operators. You will also learn about correlated subqueries, which are subqueries where some subquery clauses refer to column expressions in the main query.

In Sections 9.2 and 9.3, we will look at subqueries ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required