Articles Cookbook
21 Feb 2024
LearnSQL.com Team

4th Anniversary of LearnSQL.com

Time runs so fast. This week, we celebrate the 4th anniversary of LearnSQL.com. We have come a long way together and we promise to get even better in the upcoming year! Thank you for being with us. 1459 days have passed since February 23, 2020, when we launched the LearnSQL.com platform. That's 35,016 hours, or 2,100,960 minutes, if you prefer. It's been a long time, but it feels like yesterday that we started out together.
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20 Feb 2024
Gustavo du Mortier

MySQL Date Functions: Complete Analyst’s Guide

Master MySQL date functions and acquire a powerful tool to work with date and time information in your data analyses. Working with date and time data is an essential part of data analysis. Here are just three examples: Analyzing historical time series data is crucial for discovering trends and making reliable forecasts based on chronological information. Stock market analysis examines time series data extensively, especially when automated trading algorithms are employed.
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15 Feb 2024
Maria Durkin

SQL HAVING Clause: A Tutorial for Beginners

So, you're new to SQL and have just stumbled upon the HAVING clause. But what does it do? Why is it essential? In this article, we'll delve into the basics of the HAVING clause in SQL. And we’ll walk through practical exercises to enhance your understanding of its functionality. Let's start by defining Structured Query Language (SQL). SQL is a powerful and standardized programming language designed specifically for managing and manipulating relational databases; simply put, it is how we communicate with the databases that hold all of our important data.
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14 Feb 2024
LearnSQL.com Team

PostgreSQL Cheat Sheet

Here's your ultimate PostgreSQL cheat sheet! Whether you're a newbie or an experienced pro in need of a quick reference, this cheat sheet has got you covered. This PostgreSQL Cheat Sheet summarizes the key PostgreSQL commands and features you'll use often. It covers everything from how to connect to a PostgreSQL server and manage database contents, to the basic syntax for table creation and modification. It also breaks down the syntax for SELECT, INSERT, UPDATE, DELETE commands, and shows how to use different PostgreSQL functions, including text functions, numeric functions, NULL functions, and date and time functions.
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13 Feb 2024
Jill Thornhill

Integrating SQL with Python for Data Analysis

Integrating SQL with Python isn’t difficult. The two tools work together to combine the information-processing power of relational databases with the flexibility of a programming language. In this article, I will discuss the benefits of data analysis using SQL and Python, with real-world coding examples. Why do most of the best data analysis tools on the market – such as Tableau and Power BI – include both SQL and Python in their toolboxes?
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8 Feb 2024
Tihomir Babic

9 Practical Examples of SQL LEFT JOIN

LEFT JOIN is one of SQL's most common JOINs. Make sure you know all its ins and outs by going through all nine of our real-life LEFT JOIN examples. LEFT JOIN – alongside INNER JOIN – is one of the essential SQL tools you need to work with data from two or more tables. But how and when should you use it? These nine LEFT JOIN examples will point the way.
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5 Feb 2024
Martyna Sławińska

MySQL Practice: Best Exercises for Beginners

These 15 MySQL exercises are especially designed for beginners. They cover essential topics like selecting data from one table, ordering and grouping data, and joining data from multiple tables This article showcases beginner-level MySQL practice exercises, including solutions and comprehensive explanations. If you need to practice … Selecting data from one table Ordering and grouping data Joining data from multiple tables … these 15 tasks are just for you!
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1 Feb 2024
Jakub Romanowski

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 LearnSQL.com 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.
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1 Feb 2024
Jakub Romanowski

The Best Online SQL Editors

When it comes to online SQL editors, you have lots of options. Find out what features you should look for and what editors we prefer in this article. In this article, I'm going to share my insights on online SQL editors. These handy web-based tools have made my SQL query execution and database management tasks much simpler and more accessible – especially when compared to traditional desktop software. I'll discuss their key features and offer guidance on choosing the right one for different needs, whether you're a beginner or an experienced user.
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31 Jan 2024
Maria Durkin

This Advanced SQL Course Will Boost Your Career!

Can you already create pretty good SQL reports? Do you want to take it a step further? In this article, I'll explain how an advanced SQL course can propel you (and your career) to the next level. Since you are looking for information about SQL, you probably already know how important data is nowadays. Very few companies can stay on the market without using the power of data or basing their strategic decisions on it.
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