Hour 9. Summarizing Data Results from a Query

What You’ll Learn in This Hour:

What functions are

How functions are used

When to use functions

Using aggregate functions

Summarizing data with aggregate functions

Results from using functions

In this hour, you learn about SQL’s aggregate functions. You can perform a variety of useful functions with aggregate functions, such as getting the highest total of a sale or counting the number of orders processed on a given day. The real power of aggregate functions will be discussed in the next hour when we tackle the GROUP BY clause.

What Are Aggregate Functions?

Functions are keywords in SQL used to manipulate values within columns for output purposes. A function is a command normally used ...

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