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Top 9 SQL GROUP BY Interview Questions

pubsub.slavino.sk / learnsql · Tuesday, 17 May, 2022 - 16:00

Preparing for an SQL job interview? This guide will walk you through nine basic, intermediate, and advanced GROUP BY questions that you may have to answer. There are common GROUP BY questions that pop up in a lot of SQL job interviews; in this article, we’ll explain how to answer them. If you are a data analyst or another data professional preparing for an interview, this article aims to help you out.

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What Are Window Functions in SQL?

pubsub.slavino.sk / learnsql · Thursday, 12 May, 2022 - 16:00

In this article, we discuss what window functions are and how they help you do your job as a data analyst or specialist. No, window functions have nothing to do with the operating system. The window here refers to a set of rows over which the function aggregates data. To learn how window functions work, what functions there are, and how to apply them to real-world problems, it’s best to take the Window Functions course.

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The Complete Guide to the SQL WHERE Clause

pubsub.slavino.sk / learnsql · Tuesday, 10 May, 2022 - 16:00

Learn how to use the SQL WHERE clause to filter rows. In this comprehensive article, we cover comparison operators and the BETWEEN, IN, LIKE, AND, OR, and NOT operators. Filtering output rows is one of the first things you need to learn when starting your SQL journey. In this guide, we’ll see how to use the SQL WHERE clause to filter rows in different scenarios. We’ll cover basic and some more advanced use cases.

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Why Should Every Data Analyst Know SQL?

pubsub.slavino.sk / learnsql · Thursday, 5 May, 2022 - 16:00

In the 1980s and 90s, it was the emergence of ERPs, processing a few thousand transactions a day. Now, sophisticated Cloud-based systems work with billions of transactions each day. How data is captured and handled has come a long way! Anybody who understands how to use this data has an edge. The good thing is that while the technology working in the background has become more complex, we don’t necessarily need to understand the underlying system’s details to use it.

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Free SQL Course of the Month – PostgreSQL INSERT, UPDATE, and DELETE Commands

pubsub.slavino.sk / learnsql · Tuesday, 3 May, 2022 - 16:00

Do you want to be a data engineer or data analyst? Do you work with databases daily and need to expand your skill with the basics of data manipulation? You've come to the right place. For May 2022, our SQL course of the month is PostgreSQL INSERT, UPDATE, and DELETE Commands! Learn SQL for FREE! How do you get this free PostgreSQL course in May? Create a free LearnSQL.

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New Monthly SQL Practice for May 2022!

pubsub.slavino.sk / learnsql · Monday, 2 May, 2022 - 13:00

Ready for our new SQL challenge? This time, we have prepared some slightly more difficult SQL tasks. Here’s the May’s SQL Practice course! This time, you will be helping Tiffany, the owner of an online course website. She’d like to analyze her business data – it’s the perfect opportunity to use your SQL skills. Can you find the average number of students enrolled in a course? Calculate the average number of total hours spent by all students on a course?

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How to Update Only the First 10 Rows in SQL

pubsub.slavino.sk / learnsql · Wednesday, 27 April, 2022 - 16:00

Real-world databases require continuous updating. Often, you need to update specific records; you may even want to update only the first row, or the first 10, 100, or 1000 rows. Let’s explore how to update rows for a specified quantity from the top in SQL. What Is the SQL UPDATE? In SQL, an UPDATE statement modifies existing records of a table. You may choose to update entire columns or update rows filtered with a WHERE statement.

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Top 5 MySQL Query Tools

pubsub.slavino.sk / learnsql · Tuesday, 26 April, 2022 - 16:00

Are you looking for a software solution that will make working with the MySQL database even easier? In this article, I’ll tell you about five highly recommended query tools that will save you time. MySQL may already be familiar to you as the most popular open-source relational database management system (DBMS). It works in most applications, which is why the last Stack Overflow report rated MySQL as the most used database.

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The SQL Syntax Is Simple: True or False?

pubsub.slavino.sk / learnsql · Thursday, 21 April, 2022 - 16:00

Are you contemplating learning SQL but are concerned about how difficult it may be, especially if you have no prior coding experience? If so, you are not alone. In this article, I show you how simple SQL is and that it is worth your time learning it. You just need to know how to approach it properly. Many people carry the notion that learning SQL is much like learning other programming languages.

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