Articles Cookbook
20 Oct 2021
Marcin Koryszewski

2021’s Most Popular Databases

What was the most popular database in 2021? And what do you need to know to use it? If you’re learning SQL, you’re in luck. This year’s most popular database uses SQL. But the list doesn’t end there. Read our article and find out the 5 most popular databases this year. My list was based on the latest research of one of the most important platforms in the IT world: Stack Overflow.
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19 Oct 2021
Tihomir Babic

What Is a Recursive CTE in SQL?

The article that’ll show you practical examples of using recursive CTEs in SQL. If you’ve heard about SQL’s recursive CTEs but never used them, this article is for you. It’s also for you if you never get tired of recursive CTE examples. Before we dig into recursion, I’ll remind you what CTEs are and what their syntax is. Then I’ll do the same for recursive CTEs. After that, I’ll show you how recursive CTEs work in three examples.
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15 Oct 2021
Kateryna Koidan

How to Join Only the First Row in SQL

In your projects, you may encounter situations when you have many orders corresponding to one customer or many temperature observations corresponding to the same location, but you only need to join the first row with the most recent order or the most recently observed temperature to the corresponding record in another table. In this article, I’ll go through several ways to do this in SQL. The Problem There are many different scenarios where you have a one-to-many relationship between two tables and you need to join only the first match from one table to the corresponding record in another.
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14 Oct 2021
Kateryna Koidan

Still Using Excel for Data Analysis? See Why SQL Is Better!

Are you working with data and still using spreadsheets? Many people think that only programmers or professional data analysts can leverage SQL for data analysis. In this article, I’ll show how people with no IT background can use SQL for their daily work tasks. Not all people working with data have the corresponding job titles like data scientist, data analyst, or data engineer. Following the data democratization trend, almost all office workers do something with data as part of their daily duties – marketers analyze advertising campaigns, HR specialists analyze employee dynamics, auditors analyze credit portfolios, etc.
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13 Oct 2021
András Novoszáth

Read These 5 Data Analysis Books to Jump-Start Your Career

Do you want to pivot into a data analyst role, but you are unsure where to start? Do you do analytics in your job and would like to learn more about the big picture of data? Are you looking for a great data analysis book to read? In this article, you will find our selection of the best books on data analysis! If you are a business professional thinking about picking up data analytics skills, you may be wondering how you should start.
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12 Oct 2021
Andrew Bone

Numeric vs. Decimal Data Types in SQL

In standard SQL, there is a slight difference between the NUMERIC and DECIMAL data types. However, in some variants of SQL, there is no difference! This article will clear up any confusion. In this article, I’ll explain the differences and similarities between SQL’s standard NUMERIC and DECIMAL data types. Then I’ll discuss how these data types work in common SQL dialects. We’ve already posted a more general article on SQL data types; this time, we’ll drill down further on just the DECIMAL and NUMERIC data types.
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8 Oct 2021
Andrew Bone

How to Sort Values in a Specific Order in SQL

Sometimes you will be required to order your data in a particular way, and often the use of typical sort modifiers like ASC and DESC are not enough. This article will show you how to use the CASE statement to order your data exactly how you need it to be. Have you ever needed to order your data in a very specific way? One of the best methods for handling complex sorting is using CASE.
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7 Oct 2021
Tihomir Babic

How to Use CASE in ORDER BY in SQL

This article will show you how and when to use CASE in an ORDER BY clause. Have you ever used a CASE statement? I’m sure you have, at least in a SELECT statement. But have you ever used it in an ORDER BY clause? No? You will, once I show you how! Don’t worry if you’ve never used a CASE statement. I’ll show and explain it to you with a short example.
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6 Oct 2021
Karolina Niewiarowska

How SQL Helps Everyone in Your Office

I don't know about you, but I really like to make my life easier. If something can be done faster and more efficiently, especially if it's everyday, routine tasks, I’m all for it! This is where SQL works brilliantly. It's not just about complicated data analysis. Everyone in the office works with different types of data, and SQL can help anyone. How? Anything is possible once you learn SQL!
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5 Oct 2021
Kamila Ostrowska

Best Places to Practice SQL JOINs Online

You’ve just started your journey with SQL and you’re not sure what a JOIN is or where to use it. Don’t worry! In this article, you will find out what JOINs are and where you can practice them online. If you have just started learning SQL, you have a lot of topics to cover before you can call yourself a data professional. If you are serious about using SQL, you’ll have to understand JOIN – what it does, when you can use it, and what its different variants do.
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