Database Management Systems · Query languages

SQL aggregation and grouping

Collapsing many rows into one summary number per group, like a total or average per category.

Also known as: GROUP BY, HAVING, aggregate functions.

Start a lesson on SQL aggregation and grouping

Learn first

• SQL filtering and projection: Picking which rows and columns you want back with SELECT and WHERE.

Leads to

• SQL subqueries: A query nested inside another query, used as a stand-in value or filter.
• Data warehousing and OLAP: A separate database optimized for big analytical queries over historical data, not fast day-to-day transactions.

Related topics

• SQL subqueries: A query nested inside another query, used as a stand-in value or filter.
• Data warehousing and OLAP: A separate database optimized for big analytical queries over historical data, not fast day-to-day transactions.