Has online learning killed traditional learning? Can they coexist? Or, together, can they form something great? When I decided to write about traditional ways of learning, I was sure there was something to write about. But I wasn’t sure exactly what. I looked at some traditional learning and teaching methods, which gave me pause. Nearly each one turned out to be not entirely traditional. Wherever I looked, digital influences were making inroads.

A look at common errors that arise when writing code as an SQL beginner. Debugging, Headaches, and SQL If you’re new to SQL, you’ve probably already run into a myriad of errors. Don’t worry — you’re not alone. All developers make mistakes; it’s a normal part of the development process. The key to mastering any programming language, SQL being no exception, is understanding where the most common mistakes lie.

The mean (average) is one of the most valuable and most frequently used measures in descriptive statistics. Why is it so widely used, and why is it important to know how to calculate the arithmetic mean? Perhaps the most convincing argument is that the mean is used in virtually every area of life. With the arithmetic mean, you can calculate the average daily television viewing time for citizens of a given country, average volume of coffee drunk by a typical American, average annual temperature in your city, or the average amount you spend on food in a typical week.

Relational databases often store the value NULL in their tables. If you’re not familiar with NULL and what it is, you could run into unexpected problems. In this article, we’ll take a look at how the IN and EXISTS operators work with NULL. What Is NULL? In SQL, NULL is a special value indicating that a particular piece of data doesn’t exist in the database. For SQL beginners, it’s often a source of problems.

In my previous articles, I dealt with analyses of only a single variable. Now it is time to check whether two variables of interest are independent or somehow related. For example, a person’s height positively correlates with shoe size. Taller people have larger shoe sizes, and shorter people have smaller shoe sizes. You can find this and many more examples of positive associations at: http://examples.yourdictionary.com/positive-correlation-examples.html. A negative association is also possible.

A career in data science is hot right now. What is a data scientist, and how can you become one? Very few of us said “I want to grow up to be a data scientist” when we were kids. But now, in the age of Big Data and economic uncertainty, a career in data science is looking mighty attractive. If you like the idea of working with information and earning a good paycheck, read on.

Earth’s 7.5 billion people together use several billion different devices, generating an annual global IP traffic of more than one zettabyte. Out of these impressive numbers rises a new field above the others — “data science”. Is data science an inevitable reality, or will it yet be dismissed as just another “wave of the future” that never came to be? A few days ago I signed a new employment contract with my company.

Phones, emails, social media accounts, and about a hundred other things are constantly competing for our attention. Can tech tools help us stay focused? A lot of apps say that they help humans work better and faster. But the truth is that the more interactive tools we use, the more focus-shattering notifications we get. In many ways, technology has gotten us into this problem. Can it help us get out of it?

Phones, emails, social media accounts, and about a hundred other things are constantly competing for our attention. Can tech tools help us stay focused? A lot of apps say that they help humans work better and faster. But the truth is that the more interactive tools we use, the more focus-shattering notifications we get. In many ways, technology has gotten us into this problem. Can it help us get out of it?

Jane has a data problem and an overdue report. Will SQL save the day? Jane works as a business analyst for a large London bank. As she walks to the station on Monday morning, she’s thinking about last week’s unfinished work. She couldn’t get the data she needed from IT, so she could not deliver her report on a financial product’s non-performing assets. She absolutely must submit the report to her manager today; she’s already delayed it for more than a week.

You’ve started your mastery of SQL window functions by learning RANK, NTILE, and other basic functions. In this article, we will explain how to use SQL partitions with ranking functions. Mastering SQL window (or analytical) functions is a bumpy road, but it helps to break the journey into logical stages that build on each other. In the previous Common SQL Functions article, you learned about the various rank functions, which are the most basic form of window functions.

When you want to analyze data in a database, you need SQL window functions. What are they? How do they work? Read on to find out. There are two ways people use databases. One way is for the creation, modification and deletion of data. The other is analyzing the data, which means getting answers to specific questions. The more precise the questions you ask, the more tools you’ll need to answer them efficiently.

Here’s a shock: not everything in the movies is true. But these five documentaries offer interesting insights into the Internet and its people. Non-tech people tend to consider coding, hacking, and anything remotely dev-y as mysterious and magical processes. This myth is helped along by the movie industry, and there’s nothing wrong with that. Movie watchers generally like thrilling, action-packed stories, and coding can be anything but exciting. But not every good movie needs to be filled with action; some get our brains going by presenting new ideas or interesting viewpoints.

Learning from books is so 1999. Can app-based learning do any better? Do you like wasting your time? I don’t. Any time I start something, I find out how to do it efficiently. For me, this means learning new skills using apps and online learning rather than books. Online and app-based learning focuses on you, the student. This is the exact opposite of traditional learning, which is teacher-driven. There is a physical classroom and students, but the teacher plays the primary role.

Think that FROM only specifies tables in an SQL statement? Think again … When I first began to work with SQL, I saw the FROM clause as the simplest part of any query. You’d put only one table there, or may be two or more tables in the case of a join. That was all I thought about the FROM clause in those days. As I began to learn more about SQL, I discovered that there are a lot of techniques that can be used in a FROM.

What happens when a database receives commands from two different users? We look at the problems that can arise and how to avoid them. Every time you execute a statement in your database, you change the database’s state. When working in a multi-user environment with asynchronous database access, it will sometimes happen that two users are trying to change the same record at the same time. If both of their statements is an operation that changes the database’s state, this can create erroneous results.

Internet-based learning is very popular. Knowing your learning style and motivations will help you study smarter, not harder. We tend to spend a lot of time online these days. Between watching funny YouTube videos, catching up on news and celebrity gossip, and binge-watching our favorite Netflix series, we even find the time to learn new skills. But are we in a constant learning process? How can we pluck out – from the vast resources of the Internet – the exact courses and methods that will work for us (or you) personally?

There are two major camps in the relational database development world: OLTP and OLAP. In this post, we consider the differences and similarities of these two systems. First of all, both OLTP (on-line transactional processing) and OLAP (on-line analytical processing) are used in business applications, especially — although not exclusively — in data warehousing and analytics. Together, they form the two different sides of the analytics/warehousing coin: storing and manipulating the data on one hand and analyzing it on the other.

The tech sector is experiencing strong job growth. Should SQL be on your list of must-have skills? If you’re even remotely interested in finding a new job, you’ve probably noticed that IT jobs are hot. Not only are a lot of these jobs available, they offer some pretty great opportunities to challenge yourself, grow, and build new skills. And the compensation tends to be pretty awesome too. In today’s world, technology is evolving at an almost daily pace, and this is producing a flood of data that has to be managed.

Usually we try to avoid NULLs, but sometimes we need to have a NULL instead of an actual value. When this need pops up, a helpful but little-known SQL function called NULLIF makes it possible. This post will introduce you to NULLIF and demonstrate its use in two example cases. In the article How to Tackle NULLS: The COALESCE Function , we got to know the COALESCE function. It returns the first not-null expression.