This video is part of a multi-part series on mastering the SQL SELECT statement. The SELECT statement, the most often used SQL command, is easy to learn yet difficult to master. Follow along with me and level up your database query super powers!
This video covers the Aggregate Functions, GROUP BY, and HAVING clauses, specifically
- Counting rows, values in columns, and unique values in columns
- Getting sums, minimum, maximum, and averages.
- NULL handling of the aggregate functions.
- The purpose of GROUP BY
- Understanding why columns in the projection (SELECT line) must be in the GROUP BY when an aggregate it used.
- Using the HAVING clause to filter rows after the GROUP BY operation.
- Differences between HAVING and WHERE
The SQL code is available here: [ Ссылка ]
If you need to setup your own database environment, check out learn-databases! The easy way to get going and follow along with these videos. [ Ссылка ]
This video is part of the textbook Applied Database Management [ Ссылка ]
Here's the entire playlist: [ Ссылка ]
