Useful SQL Patterns: Matching Nulls by Masking Nulls

SQL patterns, matching NULLs, masking NULLs

As you start coding in SQL, you will use some statements and techniques over and over again. We call these “SQL patterns”. This series will look at the most common SQL patterns and consider how to use them. In database development, SQL developers often find themselves returning to the same SQL statements. Learning about these now, early in your SQL journey, will help you work more efficiently. Today, in the first post of this series, we will consider the match

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Oracle Top-N Queries for Absolute Beginners

It’s common to run a query using only part of a dataset – for example, the top 100 salespeople in a company. In this article, we’ll see how to use Oracle’s Top-N query method to query just these rows. Top-N queries retrieve a defined number of rows (top or bottom) from a result set. In other words, they find the best or worst of something – the ten best selling cars in a certain region, the five most popular routers,

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Understanding Numerical Data Types in SQL

Working with databases of any kind means working with data. This data can take a couple of predefined formats. As you start on your learning path with Vertabelo Academy, you will start to understand SQL’s different data types. In this article, we will cover the numeric data types of ANSI SQL. We’ll also examine some functions that convert data from one type to another.
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5 Books That Will Grow Your SQL Skills

Which books will help you build your database skills? We look at five awesome SQL books. There’s a common saying that “all wise men read books”. I would say that all professionals read books – particularly those related to their field. There are many books about databases and SQL; most are tied to specific vendors (DB2, Oracle, MS SQL) but there are also plenty that are vendor-neutral. In this article, I’m going to review a few books that I would

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OLTP vs. OLAP — What’s the Difference?

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

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A Day in the Life of an SQL Developer

Describing a “typical” day for an SQL developer is not easy. When your daily work is using various technologies to create interesting database-oriented products, very few days are alike! Each day brings a new and intriguing challenge. Nevertheless, I’ll have a go at explaining what everyday things an SQL developer might do. Morning: Arrive at Work The cornerstone of any software engineering endeavor is caffeine, and lots of it. An industry joke is that programmers are “machines for turning coffee

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