5 Mar 2024 Maria Durkin What Is CROSS JOIN in SQL? What is a CROSS JOIN in SQL, and when should you use it? We answer those questions – and give you some examples of CROSS JOIN you can practice for yourself – in this article. Imagine you're looking through your wardrobe for outfit ideas, wondering which top to wear with which bottom. When you think of the perfect outfit, you envision all of the tops and bottoms in your closet combined. Read more 22 Feb 2024 Radu Gheorghiu RIGHT JOIN in SQL: A Beginner's Tutorial Learn RIGHT JOIN, a crucial command for any SQL specialist. Our article breaks down this essential technique, helping beginners effortlessly navigate and apply RIGHT JOIN in their database queries. In SQL, RIGHT JOIN (also known as RIGHT OUTER JOIN) is crucial for handling data effectively. This article is a beginner-friendly guide to the SQL RIGHT JOIN, an essential technique for merging different data tables. We'll walk you through the specifics of RIGHT JOIN, explaining how it stands apart from other join types in managing data. Read more 10 Oct 2023 Martyna Sławińska SQL JOINs Explained: 5 Clear SQL INNER JOIN Examples for Beginners Looking for a clear explanation of joins in SQL? Check out these five SQL INNER JOIN examples! In SQL, INNER JOINs can be a bit difficult for beginners to master. But once you start working with them, you’ll learn they’re very useful! Let’s discuss five examples of SQL INNER JOINs. But first, let’s do a quick review of why JOINs matter. In relational databases, data is organized and stored within tables. Read more 21 Sep 2023 Tihomir Babic What Is FULL JOIN in SQL? An Explanation with 4 Examples What is FULL JOIN – one of the often neglected SQL join types? In this article, we’ll show you how useful FULL JOIN can be and teach you how to apply it to different scenarios. The four examples cover some of the typical uses. An SQL join is a construction for combining data from two or more tables. FULL JOIN is one of the types of joins. You’ll get the most from this article if you’re already familiar with SQL joins and how they work. Read more 5 Sep 2023 Tihomir Babic SQL Joins: 12 Practice Questions with Detailed Answers In this article, we dig into our SQL JOINS course and give you 12 join exercises to solve. But don’t worry – all the exercises have solutions and explanations. If you get stuck, help is there! This is, after all, made for practicing and learning. SQL joins can be tricky. It’s not just the syntax, but also knowing what joins to use in what scenarios. Joins are used when combining data from two or more tables in SQL. Read more 20 Jun 2023 Tihomir Babic What Is a LEFT OUTER JOIN in SQL? 4 Practical Examples Today’s article will discuss the LEFT OUTER JOIN in SQL. We’ll go through several examples of LEFT OUTER JOIN usage and compare it with INNER JOIN. A JOIN is an SQL feature that allows you to combine data from two or more tables. The nature of relational databases makes JOIN one of the most commonly used features in SQL. Why? In practice, you’ll very seldom have all the required data in one table. Read more 12 Mar 2021 Tihomir Babic SQL JOIN Topics That Require Practice Are you interested in learning how to join tables in SQL? Where do you start? Many JOIN topics require practice. In this article, we’ll explore these topics by writing codes to solve real-life situations. Hopefully, you will learn which JOIN topics require attention. To make it easier for you, the topics are divided into beginner, intermediate, and advanced. Joining two or more tables in SQL lifts data analysis to another level. Read more 3 Mar 2021 Kateryna Koidan How to JOIN Tables in SQL Do you need to display data stored in different tables? Then it’s time to use SQL JOINs! This can be a challenging topic for beginners, so I’ve prepared this comprehensive step-by-step guide on joining tables in SQL. Often, the information that you want to display is stored in several tables. In such cases, you’ll need to join these tables by specifying which rows should be combined with other rows. That’s exactly what JOIN does. Read more 1 Jan 2021 Tihomir Babic SQL JOIN Tips for Beginners If you’re a beginner and want to know how to start using SQL JOINs in your queries, you’ve come to the right place. Using the SQL JOIN clause is necessary if you want to query multiple tables. Sooner or later, you’ll have to use more than one table in a query. It’s the nature of relational databases in general – they consist of data that’s usually saved in multiple tables; in turn, these form a database. Read more 23 Dec 2020 Dorota Wdzięczna What Is an SQL INNER JOIN? How do you combine data from different tables in one query? An SQL feature called JOIN is the most common operator used to create complex queries. Learn the basics in this article. SQL allows us to select data from more than one table. In fact, the whole idea of using relational databases is selecting data from related tables. And we can use SQL’s JOIN operator to do this. There are many types of JOINs in SQL. Read more 12 Nov 2020 Marija Ilic SQL JOIN Types Explained What’s the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN in SQL? When should you use each one? We’ve got your answers right here. You want to combine data from two or more different tables, but you’re not sure how to do it in SQL. No worries. In this article, I will show you how to use the SQL JOIN clause to merge data from two tables. Read more 16 Sep 2020 Dorota Wdzięczna How to Join Two Tables in SQL Querying data from multiple tables is very common when working with relational databases. It is not difficult if you know how to use the dedicated SQL operators for doing this. In this article, you will learn how to join two tables by using WHERE and by using a special operator JOIN, and you will see how to filter rows in the result set. If you want to practice joining tables in SQL, check out our interactive SQL JOINs course. Read more 24 Mar 2020 Emil Drkušić How to Practice SQL JOINs Updated on: November 7, 2023 There is no better way to learn how to practice SQL joins than through hands-on experience. However, there will probably be obstacles along the way. I’ll cover some of these obstacles and give ideas for how to overcome them. While this article won’t turn you into SQL JOINs expert, it will show you how to become one. So, let’s start! Diving into the world of databases? Read more 8 May 2018 Ignacio L. Bisso Converting Subqueries to Joins Not all queries are alike, especially in terms of performance. In this article, we'll look at how you can convert SQL subqueries to joins for improved efficiency. When should I use SQL subqueries? Great question! Unfortunately, there's no concrete answer. SQL beginners tend to overuse subqueries. Typically, once they find that SQL construction works in one situation, they try to apply that same approach to other situations. It's only natural. Read more 23 Nov 2017 Dorota Wdzięczna SQL Hacks To Control Family Budget On Black Friday Weekend If you’re in the US, chances are you’ve been eagerly awaiting the approach of Black Friday just as much as Thanksgiving. Though the shopping frenzy takes hold of nearly everyone, some people have to stick to their budgets and shop prudently. In this article, we’ll take a look at how generating an SQL report can help you track how much your family spent shopping on Black Friday. Storing Black Friday Purchases in a Database Before we can create an SQL report, we first need some data we can use. Read more 28 Sep 2017 Dorota Wdzięczna An Illustrated Guide to Multiple Join So far, our articles in the "An Illustrated Guide" series have explained several join types: INNER JOINs, OUTER JOINs (LEFT JOIN, RIGHT JOIN, FULL JOIN), CROSS JOIN, self-join and non-equi join. In this final article of the series, we show you how to create SQL queries that match data from multiple tables using one or more join types. Join Types in SQL Queries Before we start discussing example SQL queries that use multiple join types, let's do a short recap of the join types we've covered so far, just to be sure you understand the differences. Read more 24 Sep 2017 Dorota Wdzięczna An Illustrated Guide to the SQL Non Equi Join Did you know that in SQL, a join doesn’t have to be based on identical matches? In this post, we look at the SQL non equi join, which uses ‘non-equal’ operators to match records. We’ve already discussed several types of joins, including self joins and CROSS JOIN, INNER JOIN and OUTER JOIN. These types of joins typically appear with the equals sign (=). However, some joins use conditions other than the equals (=) sign. Read more 21 Sep 2017 Dorota Wdzięczna An Illustrated Guide to the SQL Self Join What is an SQL self join and how does it work? When should it be used? We’ll provide answers to those questions! In SQL, we can combine data from multiple tables by using a JOIN operator. JOIN has several variants; we’ve already discussed CROSS JOIN, INNER JOIN, and OUTER JOIN. Most of the time, these operators join data from two or more different tables. You can practice all the different types of JOINs in our interactive SQL JOINs course. Read more 4 Sep 2017 Marija Ilic How to Track Down Duplicate Values in a Table When it comes to information management, duplicates present one of the most common challenges to data quality. In this article, I'll explain how it is possible to find and distinguish duplicate names with the help of the SQL data programming language. I really like my maiden name. The reason I like it so much is because it's rare. My maiden name (first with last) provided a unique identifier on platforms such as LinkedIn, Facebook, Twitter and similar. Read more 17 Aug 2017 Dorota Wdzięczna An Illustrated Guide to the SQL OUTER JOIN We’ve already discussed the SQL CROSS JOIN and INNER JOIN statements. It’s time to explore another: OUTER JOIN. What is it? How does it work? Let’s find out! If you’ve read our other posts, you know that you can link the data in two or more database tables using one of the many types of SQL join operator. Today, we’ll discuss the three kinds of OUTER JOIN: LEFT OUTER JOIN, RIGHT OUTER JOIN, and FULL OUTER JOIN. Read more 20 Jul 2017 Dorota Wdzięczna An Illustrated Guide to the SQL INNER JOIN What is an SQL INNER JOIN, and how does it work? Let's find out! In my last article, I discussed the CROSS JOIN operation in SQL. Today, we'll look at INNER JOIN and how to use it. Is it the same as a JOIN? How many tables can you link with an INNER JOIN? These are all good questions. Let's look at the answers! What is an INNER JOIN? Read more 7 Jul 2017 Dorota Wdzięczna An Illustrated Guide to the SQL CROSS JOIN What is an SQL CROSS JOIN statement? When should you use it? When shouldn't you use it? This post will tell you what you need to know about CROSS JOIN. You already know that you can use the SQL JOIN statement to join one or more tables that share a matching record. And if you're read the LearnSQL's post Learning SQL JOINs Using Real Life Situations, you know that there are many types of JOINs. Read more 6 Jul 2017 Francisco Claria An Introduction to Using SQL Aggregate Functions with JOINs Previously, we've discussed the use of SQL aggregate functions with the GROUP BY statement. Regular readers of the our blog will also remember our recent tutorial about JOINs. If you're a bit rusty on either subject, I encourage you to review them before continuing this article. That's because we will dig further into aggregate functions by pairing them with JOINs. This duo unleashes the full possibilities of SQL aggregate functions and allows us to perform computations on multiple tables in a single query. Read more 13 Jun 2017 Francisco Claria Learning JOINs With Real World SQL Examples The JOIN statement lets you work with data stored in multiple tables. In this article, I’ll walk you through the topic of JOIN clauses using real world SQL examples. Imagine if you could only work with one database table at a time. Fortunately, this isn’t anything we have to worry about. Once you learn the JOIN statement, you can start linking data together. In this article, I’ll use real world SQL examples that illustrate how we use JOINs, how each type of JOIN works, and when to use each type. Read more 21 Nov 2016 Patrycja Dybka SQL JOINs Explained with Venn Diagrams A SQL JOIN is a method to retrieve data from two or more database tables. This article presents a basic overview of what data from a particular SQL join will look like. A popular way of understanding SQL joins is to visualize them using Venn diagrams, so each example have corresponding Venn diagram, appropriate SELECT statement and the result table. There are a few major kinds of SQL joins: Read more 25 Oct 2016 Adrian Dembek SQL JOINs for Beginners You’re probably already familiar with simple SQL queries, such as SELECT * FROM table. Now you are wondering what to do when you have multiple tables, and you want to join them. Exactly! JOIN is the key. In this SQL JOINs tutorial for beginners, you will learn how to connect data from multiple tables. What are SQL JOINs? Databases usually have more than one table. JOINs are an SQL construction used to join data from two or more tables. Read more