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*Tag Archives for " SQL 201 "*

There are several ways to calculate a running total in SQL. In this article, we will cover two methods: Joins, and Window Functions. We’ll first look at how to calculate the running total using an INNER JOIN. By doing so, you’ll not only learn more about join conditions, but see how to take the result […]

Continue readingIn this puzzle, we’re going to learn how to write a SQL UNION without using Set Operations. Set operations allow us to compare rows from two or more tables to arrive at a result. For several classes of problems, it is much easier to use a set operation, than join data. But can we […]

Continue readingIn this puzzle, we’re going to about SQL set operations. Set operations allow us to compare rows from two or more tables to arrive at a result. For several classes of problems, is is much easier to use a set operation, than join data. Solving puzzles is a great way to learn SQL. Nothing beats […]

Continue readingIn this puzzle, we’re going to learn how to do some basic data modeling. Many of you have expressed an interest in learning more about data modeling and database design. I figure we could start with a simple case study and let it evolve from there. Solving puzzles is a great way to learn SQL. […]

Continue readingIn this puzzle, we’re going to learn about joins versus subqueries. In many queries you can substitute joins and subqueries. Yet, since each has their strengths, it isn’t wise to do so. Once you have worked through this puzzle you see some of the benefits and disadvantages of joins versus subqueries. Solving puzzles is a […]

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