POWER function
The POWER function is an exponential function that raises a numeric expression to
the power of a second numeric expression. For example, 2 to the third power is
calculated as POWER(2,3)
, with a result of 8
.
Syntax
{POW | POWER}(expression1, expression2)
Arguments
- expression1
-
Numeric expression to be raised. Must be an
INTEGER
,DECIMAL
, orFLOAT
data type. - expression2
-
Power to raise expression1. Must be an
INTEGER
,DECIMAL
, orFLOAT
data type.
Return type
DOUBLE PRECISION
Examples
The following examples use the TICKIT sample database. For more information, see Sample database.
In the following example, the POWER function is used to forecast what ticket sales will look like in the next 10 years, based on the number of tickets sold in 2008 (the result of the subquery). The growth rate is set at 7% per year in this example.
SELECT (SELECT SUM(qtysold) FROM sales, date WHERE sales.dateid=date.dateid AND year=2008) * POW((1+7::FLOAT/100),10) qty2010;
+-------------------+ | qty2010 | +-------------------+ | 679353.7540885945 | +-------------------+
The following example is a variation on the previous example, with the growth rate at 7% per year but the interval is set to months (120 months over 10 years).
SELECT (SELECT SUM(qtysold) FROM sales, date WHERE sales.dateid=date.dateid AND year=2008) * POW((1+7::FLOAT/100/12),120) qty2010;
+-----------------+ | qty2010 | +-----------------+ | 694034.54678046 | +-----------------+