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Free Course of the Month – Common Functions in PostgreSQL

Do you want to be able to use popular PostgreSQL functions and process different types of data more easily? You've come to the right place! Here is the Common Functions in PostgreSQL course. Throughout the month of February, this SQL course is absolutely FREE!

You are probably wondering why is offering a free SQL course. Well, we've been doing this for a long time. We choose one of our courses every month and give users free access to it. Why? Because we want to support your development and help you achieve your goals.

This time, you have the opportunity to learn about common functions with a free PostgreSQL course. You risk nothing, and you can gain a lot!

How can you get this course for FREE in February 2024?

  • Create a free account or log in if you already have one.
  • Start the course. You will have free access to its content until the end of February.

If you want to avoid the mistakes often made by online learners, read Kamila's great article “5 Reasons You Might Fail to Learn SQL.”

Free Course of the Month – Common Functions in PostgreSQL

What Are Common Functions in PostgreSQL?

You have probably already come across, for example, aggregate functions, while learning SQL and working on various projects. Do you remember COUNT(), SUM(), or AVG()? They help you with doing calculations, making simple comparisons, and obtaining statistics.

Do you want to know more about it? Read this Overview of Aggregate Functions in SQL.

Adrian has talked about aggregate functions on the “We Learn SQL” channel. Check it out and remember to subscribe and give a thumbs up!

PostgreSQL has many more built-in functions like this. But let's start with the very basics.

What is a function? It's a predefined piece of code – in our case, a piece of an SQL query – that performs a specific task. It really expands the functionality of basic SQL for you to do more and do it more easily.

Common functions in PostgreSQL help you write better and more complex SQL queries!

In our course, you’ll find the most used and the most useful functions. Do you want to work more efficiently and write more sophisticated code? Do you want to take full advantage of the possibilities offered by the database? Start learning today with the Common Functions in PostgreSQL course!

What Will You Learn in This Course?

Free Course of the Month – Common Functions in PostgreSQL

This course is an intermediate step between understanding the basics of PostgreSQL and having true working proficiency in PostgreSQL. Yes, you should already know the basics of SQL to take full advantage of this course.

If you are a complete novice and do not know what SELECT, SQL JOIN, and GROUP BY are, I recommend you start learning from the beginning and then come back here. For that, the best course is SQL Basics in PostgreSQL, which you can find in the SQL Fundamentals in PostgreSQL track. It is a great start to becoming a PostgreSQL expert.

By doing our Course of the Month, you ‘ll learn step-by-step the power of common functions in PostgreSQL:

  • Functions that work with text data:
    • CONCAT(), which allows you to merge multiple texts into one.
    • LENGTH(), which finds the length of a text.
    • LOWER(), UPPER(), and INITCAP(), which puts a text into all uppercase, or sentence case..
    • TRIM(), LTRIM(), and RTRIM(), which remove unnecessary characters from a text.
    • SUBSTRING(), which finds parts of a text.
    • REVERSE(), which reverses a text.
    • And many others.
  • Functions that work with numeric data:
    • How to perform arithmetic in databases and avoid common mistakes.
    • ROUND(), TRUNC(), and CEIL(), which round numbers to a specific number of digits.
    • ABS(), which computes the absolute value of a number.
    • You’ll also learn about arithmetic in databases and how to avoid common mistakes.
  • Date and time functions:
    • How you can store date and time data in PostgreSQL, how to find the current date and time, and how to convert date and time between time zones.
    • How interval arithmetic works in PostgreSQL.
    • DATE_TRUNC(), which helps you group data by specific periods of time.
    • DATE_PART(), which extracts part of a date.
    • You’ll also learn how to store and display date and time in specific formats, how to find the current date and time, and how to convert date and time between time zones.
    • Plus, you’ll see how interval arithmetic works in PostgreSQL
  • Other functions:
    • COALESCE() and NULLIF(), which makes working with NULLs
    • GREATEST() and LEAST(), which find the maximum and the minimum values among expressions within a row.

As you can see, our course is packed with information. Take your skills to the next level and use SQL functions!

Are you looking for a new job? Do you dream about a career as an SQL developer, a DBA, or an analyst? The skills acquired in this course can give you a significant advantage at your next job interview.

Moreover, most of the topics covered in this PostgreSQL course are not limited to this dialect of SQL. You can successfully apply your new knowledge in other popular databases like Oracle or MS SQL Server. You can check minor differences in syntax or function names in  your database’s documentation.

Why Choose the Common Functions in PostgreSQL Course on

The most important part of learning a skill well is practicing. This is the case with everything from running to advanced math. This is also true with writing queries in PostgreSQL.

Free Course of the Month – Common Functions in PostgreSQL

During our course, you will solve 143 interactive exercises ranging from easy to difficult. But although the tasks are demanding, you can definitely do them. You will have hints and a support team to answer your questions at any time.

What do we mean when we say that the course is interactive? We certainly don't mean what most similar SQL course platforms do. We don’t add nonsensical and boring videos of lectures to the course. Instead, we give you an online console where you can write real SQL queries and see their results live. It couldn't be more fun to learn PostgreSQL! We do everything to ensure that you have the best possible hands-on learning experience.

You don't need to install or configure anything on your computer. All you need is Internet access and your favorite browser. We'll take care of the rest.

If you feel comfortable with PostgreSQL functions, you can go a step further and learn how to create your own (user-defined) functions. We recommend our Writing User-Defined Functions in PostgreSQL course for this.

Who did we create Common Functions in PostgreSQL for? For anyone who wants to learn about common PostgreSQL functions! That includes database analysts, novice programmers, and students taking computer science classes. If you’re a manager or business owner, this course can also be a great complement to the competencies of your data workers.

Common Functions in PostgreSQL: Don't Stop Here!

If you are serious about a career in PostgreSQL data analytics, consider taking the SQL from A to Z in PostgreSQL track. You will find everything you need to work with working with relational databases.

You can go "all in'' and buy the All Forever Plan right away. You get access to all courses on our platform, including those that will be published in the future.

Isn't that great? Maybe you’re thinking about giving someone one of our courses or tracks as a gift. This may be a game-changer for someone. Give them a chance to develop professionally or change jobs!

With SQL, the possibilities are endless! Are you still messing with spreadsheets? See how you can do data better!

Free Course of the Month – Common Functions in PostgreSQL