Aggregate Functions
COUNT
Returns the number of rows matching the query criteria.
SELECT COUNT(*) FROM Customers WHERE CompanyName = 'CompanyName'
COUNT(DISTINCT)
Returns the number of distinct, non-null field values matching the query criteria.
SELECT COUNT(DISTINCT CustNum) AS DistinctValues FROM Customers WHERE CompanyName <> 'CompanyName'
AVG
Returns the average of the column values.
SELECT Company, AVG(AnnualRevenue) FROM Customers WHERE CompanyName <> 'CompanyName' GROUP BY Company
MIN
Returns the minimum column value.
SELECT MIN(AnnualRevenue), Company FROM Customers WHERE CompanyName <> 'CompanyName' GROUP BY Company
MAX
Returns the maximum column value.
SELECT Company, MAX(AnnualRevenue) FROM Customers WHERE CompanyName <> 'CompanyName' GROUP BY Company
SUM
Returns the total sum of the column values.
SELECT SUM(AnnualRevenue) FROM Customers WHERE CompanyName = 'CompanyName'