Having knowledge of databases is crucial if you want to explore a career in data. Whether you want to be a data scientist or an engineer, databases will come up at some point.
Structured Query Language, or SQL, gives developers a way to efficiently and securely store their data. SQL is a standard. This means that there are clear instructions on how you should write SQL.
SQL powers many aspects of the technologies you use every day. When you sign up to a site like Amazon, your name and email will be stored in a database. With this in mind, it’s clear that learning SQL can have a major impact on your career in technology.
This guide will discuss the best way to learn SQL online. We’ll give you a clear roadmap you can use to start your journey to mastering this exciting and powerful technology.
What is SQL?
SQL is a technology used to create and manage databases. SQL works with a type of database called a “relational database”, which are structures of data that have both columns and rows of data.
Each column in a table stores information about a category of data, such as a name or an email address. A row stores values for a particular entry. So, one row in a database could store a single user’s name and their email address.
SQL offers a wide range of features that make it a useful language to learn. These include:
- Adding, updating, and deleting rows
- Creating tables to store information
- Modifying tables to change the structure of a database
- Retrieving rows from the database
- Filtering entries in the database
The SQL language has been around since the 1970s, and since then has become a standard database technology. This shows that, once you’ve learned SQL, you should be able to use your skills for some time in the future.
Why Should You Learn SQL?
SQL is widely used. SQL can be applied in a wide range of different contexts. Here are just a few of the fields where SQL has become an essential tool:
- Social media
- Data analysis
- Scientific computing
- Web development
- Game development
This list could go on and on. No matter what your thoughts are on SQL, the language is everywhere. SQL is used for applications both large and small by companies of all sizes.
SQL is intuitive and easy to use. The SQL language is very literal and easy to use. Even if you have no background in technology, you should have no trouble mastering the fundamentals of how to use SQL.
SQL uses a syntax that is very similar to English, which means that the learning curve for SQL is smooth.
Demand for SQL developers is high. The TIOBE Index reports that SQL is the eighth most-commonly searched programming technology on the internet (as of April 23rd, 2020). This index tracks the most popular coding technologies in the world using data from search engines.
That’s not all. According to the U.S. Bureau of Labor Statistics, jobs in computer and information research are expected to grow by 16% by 2028. This growth is reported as “much faster than average.”
How Long Does it Take to Learn SQL?
So, how long does it take to learn SQL? To learn the basic SQL concepts to get started in SQL databases it can take as short as two to three weeks.
For real world applications and to really make a career out of SQL you will still need to expand your knowledge of SQL beyond the basics, but this can be done on the job.
How long it takes to learn depends heavily on how you’re learning it. Let’s take a look at some different ways to learn SQL.
How to Learn SQL Fast
So far, we’ve discussed the basics of SQL and why you should learn the language, even if you are not a programmer. But the next question we need to ask is: how do you learn SQL?
Let’s walk through a few steps you should follow when starting to learn SQL.
Step 1: Start with the Fundamentals
While you may have big ideas about how you can use SQL, you need to start small and master the fundamentals first. Luckily, because SQL is so widely used, there is no shortage of resources you can use to learn the basics of the programming language.
Your first step should be to explore the syntax of SQL and its queries and commands. Then, once you feel comfortable with those topics, you’ll be ready to start investigating more complex usages of SQL. Here are the main topics you should explore as you start your learning journey:
The term “manipulating data” may sound confusing, but in simple terms, it means learning how to add, change, and remove data in a database.
The first step to mastering SQL is learning how to write an SQL statement. A statement is a command sent to the database. The statement instructs a database to perform a certain action.
Here are the main topics and keywords you should learn:
SQL allows you to write queries that filter out data based on a set of conditions. For instance, you may only want to search for email addresses that begin with “s” in a database. You should explore how to write queries using the query keywords offered by SQL.
Here are some topics you should explore:
As we discussed earlier, SQL is often used for data analysis. As a result, SQL offers a number of different functions that allow you to perform mathematical operations on the data in a database.
These functions, which allow you to retrieve insights based on the data stored in a database, are called “aggregate functions.”
Here are the main topics you should learn when exploring aggregate functions:
In SQL, it is possible to work with multiple different tables at the same time and run queries that reference those different tables. In fact, this is an important part of maintaining a well-structured database. That’s where connecting tables come in. Connecting tables allow you to work with multiple sources of data contained within different tables.
Here are the main topics you should learn about when you’re ready to explore connecting tables:
- Why you should connect tables
- INNER, LEFT, and CROSS JOINs across multiple tables
- UNION statement
- WITH statement
- Primary keys and foreign keys
Where to Learn SQL Free
The next question you’ll have is: where can I learn about SQL? To help you get started on your learning journey, here are a few online intro to SQL resources that will help you understand SQL:
- Career Karma’s Introduction to SQL series
- Learn SQL by Codecademy
- edX SQL courses
- Intro to SQL: Querying and Managing Data by Khan Academy
- The Manga Guide to Databases
- SQL Cookbook by O’Reilly
- Intro to Relational Databases by Udacity
- Interactive tutorials on SQLBolt
These resources cover all the basic topics you need to know when building SQL knowledge. Once you’re ready, you can take the next step on your journey: work on a project.
Step 2: Work on an SQL Project
There is no better way to practice SQL code than to work on a real-world project. This allows you to work on projects that interest you, instead of projects that are listed in an online SQL course or tutorial.
Once you’ve mastered the fundamentals, you should start to think about an idea that you want to bring to fruition that requires SQL. For example, you may want to build a database for your blog, or you may want to analyze an interesting dataset you found online.
Are you looking for ideas to help you get started? Here are a few that you could explore:
- Inventory control management system
- Restaurant order management system
- Employee records storage system
- Airline reservations system
- Online shopping cart
Instead of building your own database, you could use tools like Kaggle to find a dataset. You can use SQL to analyze the dataset you find.
The limit to the project you decide to pursue is your own imagination. Of course, you should start small. Make sure you do not take on too many tasks at once. You can scale up your projects to use more queries and more complex SQL commands when you feel comfortable.
Step 3: Document Your Learning
It can be tempting to write an elaborate SQL query, download its results, and call it a day. Once you’ve written a query, you’ll have generated the data you need.
This approach skips one key part of the development process: documentation. Writing documentation allows you to analyze your findings and test your results. You’ll learn to validate whether an outcome of a query or project was what you expected.
When you’re getting started, your documentation can be as simple as taking notes throughout your development process.
Ask yourself questions like: “Why did I write this query using these statements?” and “Is there a more efficient way to accomplish this task?” These questions will help you flex your learning muscles and keep track of why you have made certain decisions.
Writing documentation can help you reflect on your project. After you’ve written a query, you can go back and read the documentation you have written.
This will help you better understand why you approached a problem in a certain way. You’ll be in a good opsition to evaluate whether the result of your project is in fact what you were looking to create.
Step 4: Write Reports
Writing reports is a more intensive way of documenting your work, but it is an important part of working with SQL. You’ll have everything you need to write an insightful report on your findings once you have written a query.
Reports serve a couple of purposes. In a professional development environment, managers and data analysts prefer to work with reports after a dataset has been analyzed. This is because reports are written in a way that allows anyone to understand their contents who have the relevant background knowledge. You don’t usually need to have SQL experience to read a report.
Businesses rely on reports from their engineers and data analysts to make decisions. And that’s not all! Writing reports can help you refine your thinking about a particular problem.
Step 5: Share Your Work
Documenting your work lets you seek feedback from other people.
There are a couple of ways you can share your work when you’re learning SQL. If you are using SQL on the job, you may want to seek feedback on your work from co-workers. Or you may want to write a series of blog posts to hold yourself accountable while you work on a project.
Blogs are a great way to share your work because anyone can read them at any time. People who are just starting to learn SQL could come across your post and use it to help themselves learn. Or an SQL expert could land on your page because they are stuck with a problem. They might reach out with a few comments on how to improve your work.
One of the people who read your blog may even be a recruiter or a hiring manager. They could help you break into a career in tech if you’re not already in a technical position.
If you’re not ready to start a blog, you could also share your queries and projects in a community such as Dev.to. Or you could join an SQL-specific community and share your knowledge.
Learning SQL can be time-consuming, but it is a worthy investment. It doesn’t matter if you want to be a marketer or work in data science. SQL is everywhere in technical careers that involve working with data sets.
We mentioned how SQL has become a crucial technology for data analysis, even among people who don’t know how to code. This is worth repeating because, unlike many other programming languages, there are very few technical barriers to entry. If you are ready to commit to learning SQL, you’ll have no trouble getting started.
As you proceed through your learning journey, you can start to take on more complex projects, and learn how to fine-tune your queries.