Book Image

Learn SQL Database Programming

By : Josephine Bush
5 (1)
Book Image

Learn SQL Database Programming

5 (1)
By: Josephine Bush

Overview of this book

SQL is a powerful querying language that's used to store, manipulate, and retrieve data, and it is one of the most popular languages used by developers to query and analyze data efficiently. If you're looking for a comprehensive introduction to SQL, Learn SQL Database Programming will help you to get up to speed with using SQL to streamline your work in no time. Starting with an overview of relational database management systems, this book will show you how to set up and use MySQL Workbench and design a database using practical examples. You'll also discover how to query and manipulate data with SQL programming using MySQL Workbench. As you advance, you’ll create a database, query single and multiple tables, and modify data using SQL querying. This SQL book covers advanced SQL techniques, including aggregate functions, flow control statements, error handling, and subqueries, and helps you process your data to present your findings. Finally, you’ll implement best practices for writing SQL and designing indexes and tables. By the end of this SQL programming book, you’ll have gained the confidence to use SQL queries to retrieve and manipulate data.
Table of Contents (24 chapters)
Section 1: Database Fundamentals
Section 2: Basic SQL Querying
Section 3: Advanced SQL Querying
Section 4: Presenting Your Findings
Section 5: SQL Best Practices

Using advanced joins

MySQL includes some more advanced joins such as cross, natural, and self joins. These will be discussed in the following sections.

Understanding what a CROSS JOIN is and how to use it

A CROSS JOIN is like an INNER JOIN without the ON clause. It winds up producing results that are like multiplying each table with the other table. This is also referred to as a Cartesian result. A CROSS JOIN will return a combination of every row from two tables. This join will result in a lot of rows returned. It may result in your query never returning results because it's too intensive for the database system to return the results.

To CROSS JOIN two tables, use the following syntax:

SELECT column(s)
FROM table1...