Hour 10. Sorting and Grouping Data
What You’ll Learn in This Hour:
• Why you would want to group data
GROUP BY clause
• Group value functions
• The how and why of group functions
• Grouping by columns
GROUP BY versus
You have learned how to query the database and return data in an organized fashion. You have also learned how to sort data from a query. During this hour, you learn how to break returned data from a query into groups for improved readability.
Why Group Data?
Grouping data is the process of combining columns with duplicate values in a logical order. For example, a database might contain information about employees; many employees live in different cities, but some employees live in the same ...