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)
1
Section 1: Database Fundamentals
7
Section 2: Basic SQL Querying
11
Section 3: Advanced SQL Querying
16
Section 4: Presenting Your Findings
19
Section 5: SQL Best Practices

Creating and using triggers

A trigger is a set of actions that run after you insert, update, or delete data. Triggers are created on tables. You can use triggers to enforce business rules for data, audit data, or validate data.

There are a few different types of DML triggers:

  • BEFORE INSERT: This causes the trigger to run some logic before you insert data into the table.
  • AFTER INSERT: This causes the trigger to run some logic after you insert data into the table.
  • BEFORE UPDATE: This causes the trigger to run some logic before you update data in the table.
  • AFTER UPDATE: This causes the trigger to run some logic after you update data in the table.
  • BEFORE DELETE: This causes the trigger to run some logic before you delete data from the table.
  • AFTER DELETE: This causes the trigger to run some logic after you delete data from the table.

Additionally, you can create multiple triggers...