16 Dec 2021 Kamil Bladoszewski Is SQL Case-Sensitive? Is SQL case-sensitive? The question seems simple, and you may think it’s a yes-no question. However, the answer depends on multiple factors. Let’s take a look at the possible answers. First of all, this question can be understood in multiple ways. Which part of SQL are you asking about? Do you mean keywords (e.g., SELECT, WHERE, etc.), table and column names, or values in the columns? Which database management system (DBMS) do you have in mind? Read more 11 Jun 2020 Kamil Bladoszewski What’s an SQL Inline Query? Have you ever heard the term “inline query”? How are they different from subqueries and derived tables? Have you looked this up in numerous places and still don’t know the answer? Let’s embark on a journey and find out together! The first time I heard the term “inline query”, I was a little bit surprised. It doesn’t sound like one of SQL’s nuances and I thought I knew all the basic concepts. Read more 22 May 2020 Kamil Bladoszewski Subquery vs. CTE: A SQL Primer Have you ever wondered about the differences between a subquery and a common table expression (CTE) in SQL? The concepts seem very similar, but knowing the difference – and when to use each one – will help you write efficient and readable queries. First, we’ll explain the concepts underlying subqueries and CTEs. Then we’ll look at a few examples and finally analyze the pros and cons of each technique. Read more 21 Apr 2020 Kamil Bladoszewski How to Join 3 Tables (or More) in SQL Updated on: April 19, 2024 Using JOIN in SQL doesn’t mean you can only join two tables. You can join 3, 4, or even more! The possibilities are limitless. The best way to practice SQL JOINs is LearnSQL.com's interactive SQL JOINs course. It contains over 90 hands-on exercises that let you refresh your SQL JOINs knowledge. It covers a wide range of topics from simple 2-table JOINs, through joining multiple tables and using OUTER JOINs, to joining a table with itself. Read more 25 Mar 2020 Kamil Bladoszewski How to Rank Rows in SQL: A Complete Guide Don’t struggle with SQL ranking functions anymore! This article will guide you through the most common ranking use cases. Rankings are used around us every day. Sports tournaments, the best movies and TV series on Netflix, stores with the cheapest products—these are only a few examples of rankings you might’ve seen recently. Using SQL RANK functions might be hard sometimes. The variety of different constructions is enormous. You can easily get lost in everything there is to learn about ranking. Read more