Aggregate Functions

august 8, 2018.

An aggregate function allows one perform a calculation on a set of values to return a single scalar value. Commonly used ones include:

COUNT() => number of rows with non-empty values
SUM() => sum of all values in a column
MAX() / MIN()
AVG()
ROUND() => e.g. – ROUND(columnName, decimalPlaces)
GROUP BY => groups identical data into groups
HAVING => limits result of a query based on aggregate property.