The Complete Beginner’s Guide to SQL Fundamentals

If you're new to SQL, you've come to the right place. LearnSQL.com is a fantastic resource for learning SQL from the ground up. Before you start using SQL, it's helpful to understand what it is and how databases function. This guide provides a clear introduction to SQL fundamentals.

At first, SQL may seem complex, but with the right approach, it becomes much easier to grasp. This guide will simplify the basics of SQL, making it accessible for beginners. Whether you're looking to gain a basic understanding or expand your skills with more advanced concepts, this guide covers the key areas you'll need.

I’ll explain the core ideas step by step, so even if you're starting from scratch, you'll soon feel comfortable working with databases.

Our SQL Basics course is the ideal way to begin. It’s designed specifically for beginners, offering a clear introduction to the essentials. With this course, you’ll build a strong foundation to support your future learning.

Database and SQL Fundamentals: Understanding the Basics

Let’s begin our guide to SQL with basic definitions. You might have already heard that SQL is used with databases. What exactly is a database? In the most general sense, it is an organized collection of various kinds of data. Think of it as a place where you can keep information – e.g. a list of website users’ passwords and profile names; an online store’s transaction history; or a hospital’s patient records. Such data can be stored in various ways: simple text files, spreadsheets, or in databases.

Now, when we talk about SQL, we're referring to the Structured Query Language, a powerful tool that interacts with these databases. It's the language that allows us to retrieve, update, and manipulate the data stored within. Imagine having a vast library of books, and SQL being the librarian who knows exactly where each book is and can fetch it for you on command.

SQL, originally named "SEQUEL", was developed in the 1970s by Donald D. Chamberlin and Raymond F. Boyce at IBM. It was designed to manage and retrieve data. Over time, "SEQUEL" was shortened to SQL. More on the history of this awesome programming language you can read in the article The History of SQL – How It All Began.

The introduction of SQL was a game-changer. Before SQL, databases used various unique languages, complicating data management. Now, SQL stands as the standard language for database systems like MySQL, PostgreSQL, and Oracle. In our data-driven world, SQL's role in accessing and analyzing vast amounts of data is crucial for many sectors, from businesses to governments.

We also talk about what SQL is on our YouTube channel "We Learn SQL". Check it out. Remember to subscribe.

SQL Fundamentals in DBMS: How Databases Are Managed

Going further with our guide to SQL, it's essential to understand the role of a database management system (DBMS). At its core, a DBMS is a specialized computer program, akin to familiar tools like Internet browsers or word processors. Its primary function is to manage databases, allowing users to configure, add, delete, and display data efficiently.

Among the myriad of DBMS programs available, some have risen to prominence due to their robust features and widespread adoption. Oracle, for instance, is renowned for its scalability and is often the choice for large enterprises with complex database needs. PostgreSQL, an open-source RDBMS, is celebrated for its extensibility and compliance with standards.

MySQL, another open-source option, is known for its reliability and is commonly used in web applications. Microsoft SQL Server, developed by tech giant Microsoft, integrates seamlessly with other Microsoft products and offers a comprehensive solution for businesses of all sizes. Lastly, SQLite stands out for its lightweight nature, often being the go-to for mobile applications and smaller projects due to its serverless, self-contained setup. Want to know more about the most popular databases go here.

Each of these DBMS programs brings unique features to the table, catering to various needs and applications. Whether you're managing a multinational corporation's data infrastructure or developing a new mobile app, there's a DBMS tailored to your requirements.

Don't know what to choose? Check out the latest database trends.

SQL Fundamentals: Database Tables

You have probably used a spreadsheet program (like Excel). In a spreadsheet, there are columns and rows which you can fill with data. A database is a set of tables that look similar to Excel sheets – they consist of columns that always store one kind of data and rows that hold information about specific items. Below is an example of a very simple table in a database.

table: movie

When you open an Excel sheet, you can see all the data right away. In order to access data in a database, however, you need to specify what you want to see. That’s where our guide to SQL proceeds to the notion of a programming language.

What Does SQL Do?

IBM invented SQL, or Structured Query Language, in the 1980s as a way to communicate with databases. Although SQL requires a strict syntax, or order of words and commands, it is designed to be human readable. This means that even non-programmers can figure out the meaning of some simple SQL queries. For instance, the statement below…

SELECT title, director FROM movie WHERE release_year=1994;

…tells the database to display the titles and directors of movies (SELECT title, director) that are stored in the movie table (FROM movie) and were released in 1994 (WHERE release_year=1994).

SQL keywords are often written in uppercase for greater readability. You can see some of them in the statement above: SELECT, FROM and WHERE. Each keyword has a specific meaning and must appear in a certain order for the database to process it.

Advanced SQL statements allow you to create multiple filters, group rows, join tables, calculate averages and sums, and do much more. You can learn all of these skills in our interactive SQL courses.

A guide to SQL cannot omit the pronunciation issue. SQL can be pronounced two different ways. You can either say each letter separately (“S-Q-L”), or say it as a single word (“sequel”). You can find out more about the history of the SQL name by reading S.Q.L. or Sequel: How to Pronounce SQL?

CRUD Operations

Another topic from the area of SQL fundamentals are CRUD operations. You may have heard that SQL supports all of them. CRUD stands for Create, Read, Update and Delete, which are the four basic operations in any database. As a database language, SQL can perform all of these operations:

• You can create new data with INSERT statements.
• You can read data with SELECT statements, as we did in the above example.
• You can update data with UPDATE statements.
• You can delete data with DELETE statements.

SELECT statements are by far the most frequently used SQL statements. This is why we recommend you take our SQL Queries course first if you have no prior experience with SQL. The remaining operations – creating, updating and deleting data – are explained in another course, Operating on Data in SQL.

Beyond SQL Fundamentals

Aside from accessing and displaying data, SQL can also be used to create new tables in a database. Good table design makes user mistakes less likely.

The SQL A to Z track is a straightforward guide that covers everything you need to know about SQL, from the basics to more advanced topics. Whether you're new to SQL or want to improve your database skills, this course will teach you how to create and manage tables, write queries, and handle more complex data tasks. Each lesson builds on the last, so you can easily follow along and understand how to use SQL in real-world situations.

Beyond the basics of SQL, this course dives into query optimization and advanced database management techniques, giving you the tools to work with large datasets and complex queries efficiently. By the end, you'll have the practical knowledge to confidently handle data analysis in any environment, making this track a valuable asset for advancing your career in data analytics.

In many ways, learning SQL fundamentals is a good place to start working with databases. Continue reading the LearnSQL.com blog for more information, or try any of our interactive SQL courses for free!