18 Jul 2024 Tihomir Babic SQL Project for Portfolio: Northwind Store SQL portfolio projects are an important part of a data analyst’s education. How do you start a project, and where do you go with the insights you discover? We’ll use the Northwind store database to answer this. Doing a solid SQL project is an essential element of any data analyst’s learning process. An SQL project is a great tool for learning, as it makes you use SQL on a real-world dataset. Read more 20 Jun 2024 Tihomir Babic SQL for Financial Reporting SQL should be part of every modern financial reporting process. It can deal with gigabytes of data and perform financial calculations in a split second. It’s time to transition from Abacus (also known as Excel!) and start using SQL in financial reporting. Data has taken a central part in business decision making. This applies even more to financial data. The main goal of businesses is to make a profit, so it’s no wonder that financial data plays a crucial role in the strategic decision-making process of any modern business. Read more 21 May 2024 Tihomir Babic SQL Window Functions Guide Every data analyst can benefit from knowing SQL window functions. They up your data analysis game and open doors to analyzing data on an entirely new level. This article is your starting point for the world of SQL window functions. SQL window functions allow you to show all the data rows and their aggregate values at the same time. Sounds a bit like GROUP BY on steroids, doesn’t it? Read more 18 Apr 2024 Tihomir Babic GROUP BY and Aggregate Functions: A Complete Overview SQL’s GROUP BY and aggregate functions are essential in data aggregation – and for analyzing data and creating reports. Let’s explore them together! In SQL, GROUP BY and aggregate functions are one of the language’s most popular features. Data aggregation is critical for data analysis and reporting; to make sense of all the data in a dataset, it often needs to be aggregated. But what is data aggregation? Put simply, it’s when you group data based on common values and perform a calculation for each data group. Read more 21 Mar 2024 Tihomir Babic 15 Tricky SQL Interview Questions for Experienced Users SQL interview questions for experienced users usually contain some trick(y) questions. Interviewers use them to test your gumption, which is typically a result of extensive experience and a high level of SQL knowledge. I will show you 15 tricky SQL interview questions (mostly coding) in this article. Mind you, these are not necessarily complex questions. Actually, that’s their main characteristic: they seem very easy and straightforward, but that’s the interviewer trying to deceive you. Read more 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. Read more 30 Jan 2024 Tihomir Babic SQL Server Date Functions: A Data Analysis Guide Date functions are the bread and butter of data analysis and reporting with SQL Server. In this guide, I will show you practical examples of the use of SQL Server date functions and how to apply them to your reports. A question for all data analysts: Do you want to be taken seriously? I’m sure you do. In that case, knowing SQL Server date functions is mandatory. Date and time data types are ubiquitous in databases, as they are essential for reporting. Read more 26 Dec 2023 Tihomir Babic Basic SQL Query Practice Online: 20 Exercises for Beginners These 20 exercises are just what beginners need for SQL query practice. Try to solve each of them, and then look at the solutions. If something needs to be clarified, there are explanations for each solution. In this article, there’ll be less talking than usual. Instead, you’re going to write the answers to SQL practice queries. (Don’t worry; we’ve included the solutions if you get stuck.) The whole point is to give you, as a beginner, plenty of opportunities for SQL query practice. Read more 28 Nov 2023 Tihomir Babic What Are SQL Window Functions? Need to up your data analysis game? Learn these SQL window functions here and you’ll take your analysis skills to the next level. Practice exercises and detailed explanations included! When I first heard about SQL window functions, I thought it was some strange marriage between SQL and Windows. I was wrong. The SQL window functions have nothing to do with that famous operating system. They are SQL functions that do computations on the set of rows related to the current row. Read more 19 Oct 2023 Tihomir Babic Top 29 SQL Server Interview Questions Looking for an SQL Server job? Review these 29 must-know SQL Server interview questions and you’ll be well-prepared. And don’t worry about looking up the answers – we provide them, too! Microsoft SQL Server's first version was released in 1989 and has a rich history. It has come a long way since then, becoming one of the most used database engines in the data industry. In the last ten years, it’s been the third most popular database engine. Read more «« « 1 2 3 … 9 » »»