As we covered in Chapter 1, Introduction to Relational Database Management Systems, relational databases contain tables that are related to one another. Once you need to query more than one table, you can rely on these relationships to join the tables together. There are three types of table relationships: one-to-one, one-to-many, and many-to-many. First, let's go over how to display these relationships in a diagram.
- Title Page
- Copyright and Credits
- About Packt
- Contributors
- Preface
- Section 1: Database Fundamentals
- Introduction to Relational Database Management Systems
- Installing and Using MySQL Workbench
- Understanding Data Types
- Designing and Creating a Database
- Technical requirements
- Creating a database
- Understanding table relationships
- Creating a table in the database
- Understanding indexes
- Summary 
- Further reading
- Questions
- Importing and Exporting Data
- Section 2: Basic SQL Querying
- Querying a Single Table
- Technical requirements
- Using the SELECT statement and FROM clause
- Understanding the SELECT statement and the FROM clause
- Learning the correct order of other clauses you can use with SELECT
- Understanding the different ways to query with a SELECT statement
- Learning how to use column aliases
- Using the USE statement
- Learning how to use the DISTINCT clause 
- Learning how to use the LIMIT clause
- Learning how to save a SQL query to a file
- Learning how to open a SQL file
- Learning how to add comments to your SQL code
- Using the WHERE clause
- Using the ORDER BY clause
- Using indexes with your queries 
- Summary
- Questions
- Further reading 
- Querying Multiple Tables
- Technical requirements
- Understanding joins 
- Using INNER JOIN 
- Using OUTER JOIN 
- Using advanced joins 
- Understanding set theory
- Using indexes with your queries 
- Summary 
- Questions
- Further reading 
- Modifying Data and Table Structures
- Section 3: Advanced SQL Querying
- Working with Expressions
- Technical requirements
- Using expressions
- Using statistical functions
- Using generated columns 
- Summary 
- Questions 
- Further reading 
- Grouping and Summarizing Data
- Advanced Querying Techniques
- Technical requirements
- Using subqueries
- Understanding the different types of subqueries and their usage
- Using non-correlated subqueries 
- Using a non-correlated subquery in the WHERE clause
- Using a non-correlated subquery in the SELECT clause
- Using a non-correlated subquery in the FROM clause
- Using INSERT, UPDATE, and DELETE with non-correlated subqueries
- Differences between non-correlated subqueries in other relational database management systems (RDMSes)
- Using correlated subqueries 
- Using non-correlated subqueries 
- Understanding the different types of subqueries and their usage
- Using common table expressions
- Using query hints and transaction isolation levels
- Summary 
- Questions 
- Further reading 
- Programmable Objects
- Technical requirements
- Creating and using views
- Creating and using variables
- Creating and using stored procedures
- Creating and using functions
- Creating and using triggers
- Creating and using temporary tables
- Summary 
- Questions
- Further reading 
- Section 4: Presenting Your Findings
- Exploring and Processing Your Data
- Technical requirements
- Exploring your dataset
- Processing your dataset
- Summary 
- Questions 
- Telling a Story with Your Data
- Section 5: SQL Best Practices
- Best Practices for Designing and Querying
- SQL Appendix
- Assessments
- Other Books You May Enjoy
Understanding table relationships
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