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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