Using Subqueries

Introduction

Using Subqueries

In this module, you will explore the concepts of using subqueries in SQL SELECT statement. It also includes solving different types of problem that can be resolved using a subquery. Also, there are different types of subqueries used along with different types of operators. Various SET Operators used to combine multiple queries into a single query.

• Define Subqueries
• Troubleshooting with Subqueries
• Types of Subqueries
• Write Single Row and Multiple Row Subqueries
• SET Operators
• Combine Multiple Queries with SET Operators

Exercise 1 - Define Subqueries

In this exercise, you will learn the following about Subqueries:

• Establishing a connection to the database
• Parent Query Vs Subquery
• Classes of Subquery - Inline View and Nested Subquery

Exercise 2 - Troubleshooting with Subqueries

In this exercise you will learn the following about subqueries:

• Generate a Table from Which to SELECT
• Generate Projection Columns
• Generate Data for an INSERT, UPDATE or DELETE

Exercise 3 - Types of Subqueries

In this exercise you will learn the following about the Subqueries:

• Single row subqueries
• Multiple row subqueries
• Correlated subqueries

Exercise 4 - Write Single Row and Multiple Row Sub Queries

In this exercise you will learn the following about subqueries:

• Single row operators
• Multiple row operators

Exercise 5 - SET Operators

In this exercise you will learn the following about Set Operators:

• Understanding Set Operators
• Using SET Operators

Exercise 6 - Combine Multiple Queries with SET Operators

In this exercise you will learn the following about Set Operators:

• Using the Four Types of SET Operators