Data Modeling Archives

Having a good understanding of data modeling enables you to write better queries. Use the articles found on this page to familiarize yourself with these concepts such as database normalization.

I would start out by reading Keep is Simple: Easy To Understand Data Modeling Concepts, once you have become familiar with those concepts, I would highly recommend reading Database Normalization Explained in Simple English.

Once you are familiar with the concepts, then check out

Data Modeling Principles in Action, it will put some of the theory in to practice.

All the examples for this lesson are based on Microsoft SQL Server Management Studio and the sample databases AdventureWorks and WideWorldImporters. You can get started using these free tools using my guide Getting Started Using SQL Server

What is the difference between a primary and unique key?

In this article we learn the difference between a primary and unique key, and why both are important to maintaining a relational database structure. All the examples for this lesson are based on Microsoft SQL Server Management Studio and the AdventureWorks2012 database. You can get started using these free tools using my Guide Getting Started Using SQL […]

Data Modeling Principles in Action

In this puzzle, we’re going to learn how to do some basic data modeling. Many of you have expressed an interest in learning more about data modeling and database design. I figure we could start with a simple case study and let it evolve from there. Solving puzzles is a great way to learn SQL. […]

What is the Difference between a Primary Key and a Foreign Key?

In this article we learn the difference between a primary key and a foreign key, and why both are important to maintaining a relational database structure. All the examples for this lesson are based on Microsoft SQL Server Management Studio and the AdventureWorks2012 database. You can get started using these free tools using my Guide Getting Started […]

Database Third Normal Form Explained in Simple English

This is the fourth in a series of posts teaching normalization. The third post focused on the second normal form, its definition, and examples to hammer it home. Once a table is in second normal form, we are guaranteed that every column is dependent on the primary key, or as I like to say, the table serves […]

Database Second Normal Form Explained in Simple English

This is the third in a series of posts teaching normalization. The second post focused on the first normal form, its definition, and examples to hammer it home. Now it is time to take a look at the second normal form. I like to think the reason we place tables in 2nd normal form is to narrow […]

Learn about the First Normal Form and Database Design

This is the second in a series of posts teaching normalization. The first post introduced database normalization, its importance, and the types of issues it solves. In this article we’ll explore the first normal form. For the examples, we’ll use the Sales Staff Information shown below as a starting point. As we pointed out in the […]

Database Normalization Explained in Simple English

Introduction Database normalization is process used to organize a database into tables and columns. The idea is that a table should be about a specific topic and that only those columns which support that topic are included. For example, a spreadsheet containing information about sales people and customers serves several purposes: Identify sales people in […]

Keep is Simple: Easy To Understand Data Modeling Concepts

When working with SQL databases it is often useful to create diagrams of the database tables and their relationships. These may be done during the design process, as your data modeling, or once the database is created, in order to document the tables’ dependencies. As I explain various concepts in my lessons, I’ll sometimes use […]