Articles Cookbook
6 Apr 2023
Maria Durkin

Best PostgreSQL Courses for Beginners

So you want to learn PostgreSQL but aren't sure how to get started? In this article, we look at some of the best online courses available on the Internet for learning PostgreSQL, so you can get started right away! What Is PostgreSQL? PostgreSQL is used in major companies such as Apple and Instagram. You may be wondering: should I learn PostgreSQL? PostgreSQL is a popular dialect of SQL, or Structured Query Language, a programming language for accessing and managing data in relational databases.
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4 Apr 2023
Maria Durkin

How to Learn SQL in a Week

Need to learn SQL in a hurry? In this article, we’ll give you a learning path that will help you learn SQL in a week! So you want to learn SQL but don't know where to begin, how long it will take, or even if you have the time. In this article, we'll show you how you can learn SQL within a week using some resources that will get your SQL journey started in no time!
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1 Apr 2023
Jakub Romanowski

Course of the Month: SQL Reports in PostgreSQL

If you are looking for a course that takes your PostgreSQL skills to a completely different level, you've come to the right place. You can learn for free in April! We chose SQL Reporting in PostgreSQL for our Free SQL Course of the Month. It's just awesome – I'll tell you why. Do you want to be even better at SQL? Do you know the basics and want your SQL reports to be even more sophisticated?
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30 Mar 2023
Nicole Darnley

How to Use CASE WHEN in GROUP BY

Learn how you can combine SQL CASE WHEN and GROUP BY to create custom categories in your SQL queries. Raw data, by its very nature, is not always human readable. Many times, the data you’re querying is in its most unformatted form. Examples of this include codes for different business departments or product SKUs that represent specific products. To the naked eye, these codes mean nothing, so pulling them into a report is not helpful for the person reading them.
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28 Mar 2023
Tihomir Babic

How to Solve the “must appear in the GROUP BY clause or be used in an aggregate function” Error in PostgreSQL

Learn what causes one of the most common PostgreSQL GROUP BY errors and how you can fix it! As a PostgreSQL user, you surely encounter many error messages when writing an SQL code. Sometimes they are quite unclear, but you won’t need an interpreter for this one: “must appear in the GROUP BY clause or be used in an aggregate function”. This error message mentions GROUP BY and aggregate functions.
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23 Mar 2023
Jill Thornhill

How to Practice Advanced SQL Online with LearnSQL.com

Want to go from intermediate to advanced SQL user? You’ll need to practice! Here are some ways you can practice advanced SQL online. You’ve seen how SQL helps you make data-driven decisions. Perhaps you’ve even learned some advanced features. But you’d like to become an expert—and for that, you need practice, practice, and more practice. Is it possible to get advanced SQL practice online? Taking SQL to the Next Level What is advanced SQL?
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21 Mar 2023
Kamila Ostrowska

Best MySQL Courses for Beginners

SQL is among the most important languages when it comes to dealing with huge amounts of data. If your job includes analyzing or collecting data and you feel that an Excel file is not enough, you need to learn or develop your SQL skills. And if you learn SQL, you also need to know one of its most popular dialects - MySQL. If you've made the decision to learn SQL, you've come to the right place.
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16 Mar 2023
Tihomir Babic

The SQL COUNT() Function: A Detailed Guide

This guide will give you a detailed explanation (with examples) of all the typical uses of the COUNT() function. Exercises included! The COUNT() function in SQL is one of the most commonly used aggregate functions. Aggregate functions in SQL are used to calculate statistics for a group of rows: counting the number of rows in each group, computing the sum of values in a group, finding the minimum or maximum value in a group, and so on.
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14 Mar 2023
Jakub Romanowski

Learning SQL in Your Native Language is Finally Possible

Do you or someone you know speak English as a second language? Would you like to learn SQL online in your preferred language? Good news! Our awesome SQL courses are now available in French, Spanish, German, Italian, and Portuguese! SQL, or Structured Query Language, is a programming language used for managing and manipulating data in databases. It's an essential skill for anyone working with data, whether you're a data analyst, a software developer, or just someone who wants to understand how databases work.
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9 Mar 2023
Maria Durkin

The Best Apps to Learn SQL

Let us guide you to the best apps for learning SQL on the go. They are designed to seamlessly integrate into your busy lifestyle – ensuring you develop your database skills anytime, anywhere. Are you eager to dive into SQL but unsure where to start? This article is your ultimate guide to the top apps for learning SQL. We include suggestions tailored for users of all levels, from beginners to advanced learners.
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