POWER or POW

The POWER Start of changeor POWEnd of change function returns the result of raising the first argument to the power of the second argument.

Read syntax diagramSkip visual syntax diagramPOWERPOW (expression-1,expression-2)
expression-1
An expression that returns a value of any built-in numeric, character-string, or graphic-string data type.1 A string argument is cast to double-precision floating point before evaluating the function. For more information about converting strings to double-precision floating point, see DOUBLE_PRECISION or DOUBLE.
expression-2
An expression that returns a value of any built-in numeric data type. If the value of expression-1 is equal to zero, then expression-2 must be greater than or equal to zero. If the value of expression-1 is less than zero, then expression-2 must be an integer value.

If the data type of the argument is decimal floating-point, the data type of the result is DECFLOAT(34). Otherwise, the result of the function is a double-precision floating-point number. If both arguments are 0, the result is 1. If an argument can be null, the result can be null; if an argument is null, the result is the null value.

Note

Results involving DECFLOAT special values: If either argument is decimal floating-point, both arguments are converted to DECFLOAT(34). For decimal floating-point values the special values are treated as follows:
  • If either argument is NaN or -NaN, NaN is returned.2
  • POWER®(Infinity, any valid second argument) returns Infinity.
  • POWER(-Infinity, any valid odd integer value) returns -Infinity.
  • POWER(-Infinity, any valid even integer value) returns Infinity.
  • POWER(0,Infinity) returns 0.
  • POWER(1,Infinity) returns 1.
  • POWER(any number greater than 1,Infinity) returns Infinity.
  • POWER(any number greater than 0 and less than 1,Infinity) returns 0.
  • POWER(any number less than 0,Infinity) returns NaN. 2
  • If either argument is sNaN or -sNaN, a warning or error is returned. 2

Example

  • Assume the host variable HPOWER is an integer with value 3. 
      SELECT POWER(2,:HPOWER)
    FROM SYSIBM.SYSDUMMY1
    Returns the value 8.
1 The result of the POWER function is exactly the same as the result of exponentiation: expression-1 ** expression-2.
2 If *YES is specified for the SQL_DECFLOAT_WARNINGS query option, NaN is returned with a warning