How to Learn SQL

Have you ever wondered how e-commerce sites can track all of your purchases? Or how Google remembers some of your past searches? Behind these applications is a database which stores information. To access information from a database, most people and businesses use SQL, a standard for storing data.

In this guide, we’re going to chat through how you can learn SQL. We will start with the basics: what is SQL and what jobs require SQL? Then, we will move onto where you can go to learn SQL, with reference to books and courses.

What is SQL?

Structured Query Language, or SQL (said as “es-que-el” or “see-quel”), allows you to store information in and access information from a database. SQL allows you to modify individual values in a database or entire rows. You can also remove or add new rows in a database. SQL is an international standard and to this day is one of the fundamental skills for database management.

There are many implementations of SQL. For instance, PostgreSQL, Oracle Database, MySQL, and Microsoft Access all implement SQL, too, but each tool has their own features that database administrators can use. Ultimately, however, all of these databases use a very similar syntax for creating, updating, and deleting records because they all follow the SQL standard.

Jobs that Require SQL Skills

SQL is an essential skill in any job that involves manipulating data. For instance, data scientists need to know SQL because a lot of their work involves analyzing data from databases. Below is a list of the main jobs that require SQL skills:

• Back-end web developer
• Full-stack web developer
• Data analyst
• Data scientist
• Data engineer
• Database administrator
• Systems engineer

These are only a few of the many positions that require knowledge of SQL. All of these positions involve working with data in some way, from administering a database to writing queries to manipulate the contents of a database.

What Industries Use SQL?

SQL is used in most industries that need to store data. Even Microsoft Access, which is used often in business settings and is a drag-and-drop tool, is based on SQL. Below are a few examples of industries that use databases:

• Healthcare
• Manufacturing
• Finance and banking
• Construction
• Online media
• E-commerce

Any industry that needs to keep logs of something could make use of databases. For instance, construction companies may use SQL to keep track of employee data, perhaps through a tool like Microsoft Access. Healthcare companies may use databases to keep track of patient records.

People who use technology powered by SQL may not know it because a lot of database tools abstract away from the language because SQL is not intuitive in many cases where someone may want to use a database.

Salary for SQL Developers

People skilled in SQL can demand excellent salaries. According to Glassdoor, the average database administrator, who will most likely work with SQL every day, earns $78,779 per year. The average data analyst, who is also very likely to work with SQL, earns $62,453 per year. As you get more experience working with data, your salary prospects will improve. Some positions that use SQL, like data scientist, have average salaries above $100,000 per year.

What Skills Do I Need to Master SQL

You do not need to have any knowledge of programming to learn SQL. An understanding of a programming language is helpful, but definitely not required. A good knowledge of basic mathematics is also useful as some database calculations can involve math. But, you can pick up most of what you will need to use as you learn more about SQL.

You can learn SQL even with little knowledge about programming or data science so SQL is a good entry way into data careers. Your SQL skills could take you on to a range of careers in data, if you study and work hard.

Where to Learn SQL

Where can you learn about SQL? SQL has been around for decades so it is easy to find SQL learning resources online. We have compiled a list of some of the top SQL learning resources which you can use to start learning SQL.

Learn SQL

• Author: Codecademy
• Price: Free
• Type of Resource: Course

The Codecademy Learn SQL course, which takes an estimated eight hours to complete, teaches the basics of SQL. You will learn topics such as updating data in a database, using aggregate functions, and performing both simple and more complex queries.

In the Pro version of this course ( $19.99 per month), you will be tasked with working on four interactive projects. These projects, which include creating your own table, will allow you deepen your understanding of the syntax you learn in class.

Intro to SQL: Querying and managing data

• Author: Khan Academy
• Price: Free
• Type of Resource: Course

The Khan Academy Intro to SQL Course is a great place to start your journey learning SQL. You will start by learning the basics of SQL and then move onto writing more advanced queries using statements like AND, CASE, and HAVING.

This course comes with plenty of challenges which will push your knowledge of SQL and encourage you to write queries for yourself. By the end of completing this course, you will know how to write basic and relational queries and how to modify a database.

Introduction to Databases and SQL

• Author: Raspberry Pi Foundation and Teach Computing (on FutureLearn)
• Price: Free
• Type of Resource: Course

This course will teach you how to use SQL to search for and manipulate data in a database. This course was written for beginners to databases and goes on over the course of three weeks. You will start by learning what a database is and then discuss how to use SQL. Toward the end of the course, you will explore data analytics, relationships, and adapting databases.

Introduction to Structured Query Language (SQL)

• Author: University of Michigan (on Coursera)
• Price: Free
• Type of Resource: Course

In this course, you will learn how to use SQL in the context of web development. You will start by installing PHP and SQL. PHP and SQL are often used together to create web pages capable of storing data. Then, you will learn the basics of SQL and how to design a database.

This course is excellent if you have a basic understanding of PHP and want to learn how to use SQL. In total, this course will take about 16 hours to complete, according to Coursera.

SQL Tutorial – Full Database Course for Beginners

• Author: freeCodeCamp
• Price: Free
• Type of Resource: Video

This tutorial, which lasts four hours, covers the basics of working with SQL. You will start at the very beginning and learn to install MySQL, a database client, on your computer. You will then learn how to create tablets, and insert data into tables.

This video is intense so you may find yourself pausing and coming back to concepts later. But, the instructor is eloquent in their teaching and walks you through how queries are written and how they work.

A Guide to Learning SQL

What do you need to know to become an SQL developer? That is a good question. SQL can get quite complicated but when you learn the basics you will realise that all the more complicated queries are built up with the same building blocks.

To help you master those building blocks, we have prepared a list of some beginner concepts you need to know:

• Syntax. What is a query? What is a statement? How is a query formatted? What is a row and a column? You should be able to answer these questions before you go any further in your learning.
• SELECT. You should learn how to retrieve information from a database using a SELECT statement.
• WHERE and Filtering. You should know how to use a WHERE clause and the filtering methods (operators) to choose what items you want a query to retrieve, change, or delete.
• UPDATE. UPDATE statements let you change the contents of records in a database. You will need to know how to use an UPDATE statement.
• DELETE. A DELETE statement removes a record from a database. This is an essential statement to know about.
• Aggregate Functions. You should know how to use the COUNT, SUM, MIN, MAX, and AVG functions to retrieve information about the data in a database. You will also need to know how to use the GROUP BY statement with aggregate functions.
• IN and BETWEEN. You will need to know how to use the IN and BETWEEN statements to retrieve records in a particular dataset or between a range.
• Aliases. Aliases make queries easier to read, when used properly. You should feel comfortable using an alias to assign temporary names to tables in a database when you are writing a query.

After you have learned these concepts, you will be on your way to becoming an SQL expert.

How Long Does It Take to Learn SQL?

You can start writing basic SQL statements within an hour or so of starting to study. To master the basics, you should expect to spend about a month studying, assuming you devote one hour a day in that time. If you want to become a professional developer in a field that uses SQL, you will probably need to study for a few months before you will be ready for an entry-level job that requires SQL knowledge.

Should I Learn SQL?

If you want to work in a position that is focused on data — whether that means administering databases or analyzing datasets — having a knowledge of SQL is essential. SQL knowledge is also a requirement in many back-end and full-stack web developer roles, where you will use SQL to store information from web apps.

It will not take you long to learn the basics and with the right investment of time you should have no trouble becoming an expert SQL developer. Your studying will not go unrewarded: the jobs in which SQL is heavily used all pay well. If you see yourself working with data in your career, consider spending some time learning SQL.