GROUP BY¶

The GROUP BY groups rows that have the same values in specified columns into summary rows, like aggregating data.

Syntax¶

SELECT <column1>, [ aggregate_function <column2> ]
FROM <table_name>
[ WHERE <condition> ]
GROUP BY <column_name>

Parameter	Description
`column1`	The column by which you want to group the data
`column2`	The columns to retrieve
`table_name`	The table from which to retrieve the data
`condition`	Filters the rows before grouping them
`GROUP BY column1`	Groups the rows by the values in column1

SELECT
  department_id,
  COUNT(*)
FROM
  employees
GROUP BY
  department_id;