Group by (SQL)

A GROUP BY statement in SQL specifies that a SQL SELECT statement returns a list that is grouped by one or more columns, usually in order to apply some sort of aggregate function to certain columns.

Examples:

Returns a list of Department IDs along with the sum of their sales for the date of January 1, 2000.

SELECT DeptID, SUM(SaleAmount) FROM Sales
WHERE SaleDate = '01-Jan-2000'
GROUP BY DeptID