What is the GROUP BY clause?

Parthiban Kannan

Updated on January 8, 2026

< 1 min read

The GROUP BY clause is used to group rows that share the same values.
It is mainly used with aggregate functions like SUM or COUNT.
This helps generate summarized data instead of row-level data.
In my project, we grouped sales data by product and month.
This enabled monthly revenue reporting.
Non-aggregated columns in SELECT must be included in GROUP BY.
It is essential for analytical and summary reports.