Articles Cookbook
22 Dec 2022
Marko Calasan

What Are DDL, DML, DQL, and DCL in SQL?

We explore the separation of SQL into its four principal sublanguages and explain the meaning behind each of them. When you’re learning SQL – perhaps through LearnSQL.com’s very own comprehensive SQL Basics course – you may have come across the terms DDL, DML, DQL, and DCL. And maybe you’ve gotten confused by all the acronyms. In this article, we will explain what these terms stand for and how they correspond to sublanguages that neatly divide the SQL language into four parts that function together.
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20 Dec 2022
Nicole Darnley

How to Use WHERE with GROUP BY in SQL

In this article, we’ll discuss how to combine the WHERE and GROUP BY clauses in SQL. If you’re writing SQL on a daily basis, you will quickly realize how often both WHERE and GROUP BY clauses are used. WHERE is an essential part of most queries. It allows you to filter large datasets to only the pieces you are interested in. GROUP BY is one of the most powerful tools an analyst has when aggregating data.
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15 Dec 2022
Maria Durkin

Want to Get a Data Engineering Job? Learn SQL!

So, you want to be a data engineer, but you don't know how to get there. In this article, we’ll help you understand the skills you'll need for different types of data engineering jobs. You’ll also find some data confirming that data engineer jobs are a good career choice. Data engineering and various types of data engineer jobs have become very popular in recent years. And for good reason: Next to data science, data engineering is one of the fastest-growing branches of IT.
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13 Dec 2022
Tihomir Babic

5 Practical Examples of SQL’s WITH Clause

These five practical use cases will make you want to use the SQL WITH clause daily. The WITH clause can help you write readable SQL queries  and break complex calculations into logical steps. It was added to SQL to simplify complicated long queries. In this article, we’ll show you 5 practical examples of the WITH clause and explain how using it makes SQL queries more readable. The WITH clause is also called a Common Table Expression (CTE).
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8 Dec 2022
Martyna Sławińska

How to Export Data From Microsoft SQL Server to a CSV File

When working with data and databases, it is common to export data for further processing or transport to another database. Follow this article to learn how to export data from Microsoft SQL Server to a CSV file. In this article, we first recall what a CSV file is and why you would want to export data in this format from an MS SQL Server database. Then, we cut to the chase and export data to a CSV file using both SQL Server Management Studio (SSMS) and SQL Command Line (SQLCMD).
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6 Dec 2022
Jill Thornhill

The Future of SQL

Is it worthwhile to learn SQL? Or will a language that’s over 40 years old soon be outdated? Have relational databases been eclipsed by the advent of other database solutions like NoSQL? In this article, we answer these questions. Do you need to upgrade your IT skills? What should you learn first? The choice is daunting. If you're looking to the future, you obviously want to invest your time in something that's still widely used and will continue to be in the years to come.
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29 Nov 2022
Ignacio L. Bisso

How to Choose Data Types for SQL Table Columns

Databases store data values of various kinds. For example, you may store the name of a product as a text string, the price of a product as a number, or the date a product is sold as a date value. These values – the product name, the price, and the sale date – are stored as different data types. In this article, we explain several SQL data types with real examples.
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24 Nov 2022
Kamila Ostrowska

The Most Popular Databases in 2024

If you work with data – or if you want to start – you need a database that will answer your needs. Not sure what to choose? Don’t worry! In this article, you’ll find a list of today’s most popular and efficient databases, with a quick summary of what each one does. Businesses run on data. But to get the most from that data, it needs to be stored in a structured way – usually in a database.
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22 Nov 2022
Martyna Sławińska

How to Export Data from MySQL into a CSV File

A database is a primary platform for working with data and storing data. But often, you must take your data out of the database. Read on to find out how to export data from MySQL database into a CSV file. In this article, we’ll demonstrate how to export data into a CSV file. We’ll start by introducing what a CSV file is and why we use it. Then, we’ll export data from a MySQL database into a CSV file.
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18 Nov 2022
Alexandre Bruffa

I’m a Software Developer. How Do I Learn SQL?

What do you need to know about relational databases and SQL as a software developer? In this article, we’ll explain the topics you need to know and how you can acquire this knowledge. If you are a software developer, you may have noticed that SQL skills are often required in some development roles. Although you are not a database manager or a data scientist, you will need solid SQL foundations to continue your developer journey.
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