For this post, I’ve gathered 15 of the most interesting SQL articles published in 2017. If you’re an SQL beginner and are interested in learning more about databases and SQL queries, or if you’d just like to expand your knowledge of SQL, this article is perfect for you. Let’s dive right in!
Top 3 Vertabelo Academy articles
I’ll start off the list with three of the most popular Vertabelo Academy articles.
Nowadays, you have endless options on hand for refining your SQL skills, and it can often seem overwhelming to pick just the right ones. If you want to know more about the differences between traditional and modern methods of learning SQL, or if you’re simply looking for a list of the best SQL courses and competitive programming sites, Aldo’s article is a must-read for you.
Courses are great, but sometimes a good book can take you a long way in understanding programming. If you prefer more traditional methods of learning SQL, go ahead and check out Aldo’s article. In it, he describes the five most important books that can guide you from being a total SQL beginner to a query master. Each section of the article lists a book with a short description of its contents and a measure of its difficulty level.
One of the most common operations in SQL is the self-join. It may seem trivial, but the self-join is an incredibly important topic to understand if you’re looking to master SQL. In her article, Dorota provides an in-depth guide explaining how self-joins work.
Top 12 Miscellaneous SQL Articles
Working with SQL on a daily basis requires a solid understanding of topics like
GROUP BY, and more. Below, you’ll find a list of 10 of the best articles that can help you write more efficient SQL queries.
Let’s be honest: all reports you write based on SQL queries will be pointless if you don’t indicate the absence of data. It’s a well-known fact that
NULL can help you deal with missing data, but beginners often have problems with understanding how to use
NULL properly. Markus’s article is a great guide on the SQL
NULL value. In his article, Markus describes what
NULL really is, as well as where and how it should be used.
Not every SQL beginner knows what
DISTINCT is and how it’s used. However, the
DISTINCT clause is absolutely crucial because it allows you to select only unique records from a database, which is often of interest. Haki’s article is a great guide on the subject, and it’s a must-read if you plan on getting your hands dirty with databases!
If you’ve ever written an SQL query, you’ve likely been faced with the task of selecting a specific number of records from a result set. Often, the queries written to accomplish this task are inefficient. The author of this article discusses various methods of writing efficient TOP
N queries. Even if you’re not a total beginner, this article can serve you well on your SQL journey.
How many times have you written a query using
ORDER BY with
OFFSET clauses and found that it nearly killed your database? Has your query ever taken light years to run? Why do queries sometimes slow to a near halt? This EverSQL Team article addresses the problem of slow SQL queries that rely on the
OFFSET method by testing SQL pagination scripts. It’s definitely worth a closer look if you want to speed up pagination in your future queries!
Have you ever prepared a report about products that were sold at a specific time? Or perhaps you’re looking to prepare a cost-analysis report for a company. For these tasks, you’ll need to rely on the essential
GROUP BY clause. This important clause lets you group data and then calculate values for each group. Sean presents a comprehensive guide on
GROUP BY that’s more than useful for beginners.
7. “A Probably Incomplete, Comprehensive Guide to the Many Different Ways to JOIN Tables in SQL” by JOOQ
When working with data and building complex reports that combine information from multiple tables, you need to be able to use the SQL
JOIN operation. To learn more about how you can combine data from different tables and what types of
JOINs you should use to write proper SQL queries, check out this great read by JOOQ!
Let’s say you need to prepare an analytical report on products sold in a given year, and you’re working with a table that has the columns year, amount, and category of the product. Suppose you’d like to change the table so the first row contains the category names, the first column contains the years, and the remaining fields store the amounts corresponding to each category and year. Instead of trying to convince your database administrator to restructure your database, you should take a closer look at T-SQL queries using
PIVOT to accomplish this task. Sifiso’s article is definitely worth a read!
If you’ve ever had to run a query searching for data on the employees of second level-managers or products from the same categories, you’ve likely worked with data in hierarchical relations—structures in which table records are connected through identifiers to one another. In his article, Ben shows how you can save precious time by using temporary result sets in Common Table Expressions (CTEs) and how recursive queries can be used to efficiently retrieve this kind of data.
Regardless of your motivation for learning SQL, you should be prepared for SQL interview questions if you ever plan to use the skills you develop in your career. If you’d like to know more about the most common SQL interview questions and find comprehensive answers to each of them, you should definitely read Rebecca’s article. Overall, it’s a great read for beginners and pros alike.
If you’ve ever worked with SQL Server, you’ve likely heard about the
IDENTITY property. This property is often used to create an identity column in a table. In his article, Kenneth explains how to use the
IDENTITY property and discusses the various data types an identity column can have. His article is a great resource on the subject, especially if you’ve ever found yourself trying to manage the space taken up by data types in table columns.
When dealing with
SELECT statements, you may sometimes want to pass in a column that calculates a value from a previous column. Unfortunately, the typical
SELECT statement doesn’t allow you to do this. But there’s an alternative! In this article, Pon explains how you can use virtual columns in MySQL queries.
Of course, there are many more great articles out there, but the 15 I’ve listed here can easily hold their own. I hope this article has inspired you to learn more about SQL, even if you’ve nearly mastered the language!