Examples of Aggregate Functions

Below are several examples of SQL aggregate functions. You can use these with a GROUP BY clause to aggregate rows based on the specified GROUP BY criterion. This can be a reporting tool.

COUNT

Returns the number of rows matching the query criteria.

SELECT COUNT(*) FROM Patient WHERE [name-use] = 'Bob'

COUNT(DISTINCT)

Returns the number of distinct, non-null field values matching the query criteria.

SELECT COUNT(DISTINCT Id) AS DistinctValues FROM Patient WHERE [name-use] = 'Bob'

AVG

Returns the average of the column values.

SELECT [address-city], AVG(AnnualRevenue) FROM Patient WHERE [name-use] = 'Bob' GROUP BY [address-city]

MIN

Returns the minimum column value.

SELECT MIN(AnnualRevenue), [address-city] FROM Patient WHERE [name-use] = 'Bob' GROUP BY [address-city]

MAX

Returns the maximum column value.

SELECT [address-city], MAX(AnnualRevenue) FROM Patient WHERE [name-use] = 'Bob' GROUP BY [address-city]

SUM

Returns the total sum of the column values.

SELECT SUM(AnnualRevenue) FROM Patient WHERE [name-use] = 'Bob'

COUNT

Returns the number of rows matching the query criteria.

SELECT COUNT(*) FROM Patient WHERE [name-use] = 'Bob'

COUNT(DISTINCT)

Returns the number of distinct, non-null field values matching the query criteria.

SELECT COUNT(DISTINCT Id) AS DistinctValues FROM Patient WHERE [name-use] = 'Bob'

AVG

Returns the average of the column values.

SELECT [address-city], AVG(AnnualRevenue) FROM Patient WHERE [name-use] = 'Bob'  GROUP BY [address-city]

MIN

Returns the minimum column value.

SELECT MIN(AnnualRevenue), [address-city] FROM Patient WHERE [name-use] = 'Bob' GROUP BY [address-city]

MAX

Returns the maximum column value.

SELECT [address-city], MAX(AnnualRevenue) FROM Patient WHERE [name-use] = 'Bob' GROUP BY [address-city]

SUM

Returns the total sum of the column values.

SELECT SUM(AnnualRevenue) FROM Patient WHERE [name-use] = 'Bob'