Articles Cookbook
13 Aug 2020
Adrian Więch

How to Spend Less by Mastering the Monthly Budget in SQL

Do you struggle to keep your budget under control? You must have heard about various budget planning materials available as printouts, Excel spreadsheets, smartphone apps, budget management tools, or personal finance software. In this article, we’ll show you another possibility. You’ll learn how to use databases and SQL to identify the weak points of your home budget and spend less through SQL budget analysis or monthly budget in SQL.
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12 Aug 2020
Rebecca McKeown

Is There any Demand for SQL Language Nowadays?

SQL is 46 years old. That’s 14 years older than I am, and at least 23 years older than the jar of pickles in my refrigerator. SQL is the still-hip granddaddy of the programming world. You know the one: non-ironic suspenders, twirled mustache, tattoo peeking out over his spotted socks. He may be old, but boy, is he fly. If you’ve heard of the NoSQL movement, you may be wondering: why learn SQL in this day and age?
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11 Aug 2020
Kamila Ostrowska

5 Reasons You Might Fail to Learn SQL

Learning SQL isn’t hard, but that doesn’t mean you’ll sail through, problem-free. Here are five things that might cause unwary SQL learners to fail. For me, learning SQL wasn’t always about the joy of discovery. Learning itself is not all about curiosity and the satisfaction of succeeding. Sometimes there is a sense of failure. We’re often told it is better to focus on positives. I believe this. However, it is also crucial to find out what went wrong when we don’t succeed at something.
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7 Aug 2020
Jakub Romanowski

Learning SQL When You Work and Have a Family

Do you want to learn SQL but feel you can’t squeeze one more thing into your jam-packed life? Here are my tips on learning SQL when you work and have kids. You work full-time and have a family. Daily responsibilities overwhelm you. I’ve been there. Heck, I live there. I work from home and have a family. While I was writing this article, I was also waiting for a call on Zoom, doing the laundry, and cooking some pasta for my son’s dinner.
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6 Aug 2020
Kateryna Koidan

Can you Join two Tables Without a Common Column?

Yes, you can! The longer answer is yes, there are a few ways to combine two tables without a common column, including CROSS JOIN (Cartesian product) and UNION. The latter is technically not a join but can be handy for merging tables in SQL. In this article, I’ll guide you through the different solutions with examples. When Do you Need to Join Tables Without a Common Column? Beginners just getting started with SQL are usually introduced to standard equi joins, in which two tables are combined by a common column.
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4 Aug 2020
LearnSQL.com Team

Course of the Month: Recursive Queries

Recursive Queries is one of SQL’s more advanced features. You could say they divide SQL users into beginners and experts. But how do you learn recursive queries? And why do you need them, anyway? Agnieszka Kozubek-Krycuń, Chief Content Officer at Vertabelo, is here to help. In this article, she answers your questions about our August SQL Course of the Month: Recursive Queries. Recursive queries … that sounds very serious.
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31 Jul 2020
Dorota Wdzięczna

The SQL HAVING Clause Explained

What is the SQL HAVING clause? Why do you need it, and where do you use it? We’ll explain HAVING in detail. HAVING is a very common clause in SQL queries. Like WHERE, it helps filter data; however, HAVING works in a different way. If you are familiar with the GROUP BY clause and have only heard about HAVING – or if you’re not familiar with HAVING at all – this article is what you need.
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30 Jul 2020
Ignacio L. Bisso

Using Subqueries in INSERT, UPDATE, DELETE Statements

Did you know that subqueries can also be used in UPDATE, INSERT, and DELETE statements? Subqueries in SQL are like building blocks that can be used in a variety of statements, not just SELECT. If you find subqueries useful in SELECT, read this article to find out how useful they can be in other instructions. You will be able to create much more complex and powerful SQL queries in no time!
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29 Jul 2020
Jakub Romanowski

Our 6 Favorite SQL Books

So you want to learn SQL and query databases? Great! Check out these six SQL books for an in-depth look at the language and you’ll be writing queries in no time! You take SQL courses, participate in internet discussions and forums, watch tutorials on YouTube... What else can you do to develop your skills? Sometimes it’s good to reach for old-fashioned sources of knowledge: SQL books. Which book(s) should you choose?
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28 Jul 2020
Adrian Więch

Who Is a Data Engineer?

A new kind of job has recently emerged in the IT world: Data Engineer. At first sight, it may seem very similar to Data Analyst or Data Scientist positions. However, our article explains all the important differences. We present the skills, tools, and everyday tasks of Data Engineers. We also explain how you can get started with this career path.   Thirty years ago, we typically used terms such as “Computer Scientist” when referring to anyone working with computers.
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