7.10 Mathematical Functions and Operators

Functions and operators are essential for every application. You have already used some operators in this book but in this section you will find a complete list of mathematical functions. Operators related to geometric data types will not be discussed in this chapter.

Let's look at the mathematical operators first in Table 7.2.

Table 7.2. Mathematical Operators

Operator	Description	Example	Result
+	Addition	SELECT 1+1;	2
-	Subtraction	SELECT 14-3;	11
*	Multiplication	SELECT 3*4;	12
/	Division	SELECT 18/3;	6
%	Modulo	SELECT 14%3;	2
^	Exponentiation	SELECT 2^10;	1024
|/	Square root	SELECT |/ 361;	19
||/	Cube root	SELECT 5832;	18
!	Factorial	SELECT 23!;	862453760
!!	Factorial (prefix operator)	SELECT !! 23;	862453760
@	Absolute value	SELECT @ -23;	23
&	Binary AND	SELECT 12 & 24;	8
|	Binary OR	SELECT 12 | 24;	28
#	Binary XOR	SELECT 12 # 24;	20
~	Binary NOR	SELECT 12 ~ 24;	f
<<	Binary shift left	SELECT 2 << 4;	32
>>	Binary shift right	SELECT 5 >> 2;	1

The mathematical functions are shown in Table 7.3.

Table 7.3. Mathematical Functions

Function	Description
abs(x) cbrt(double precision) ceil(numeric)	Absolute value Cube root Next integer higher than the argument of the function
degrees(double precision) exp(double precision) floor(numeric)	Convert radians to degrees Exponential function Next integer lower than the argument of the function
ln(double precision) log(double precision)	Natural logarithm Base 10 logarithm
log(base numeric, x numeric) mod(y, x) pi() pow(double precision, double precision) radians(double precision) random() round(double precision) round(value numeric, scale integer) sqrt(double precision) trunc(double precision) trunc(value numeric, scale integer)	Logarithm to specified base Remainder (modulo) of the division y/x The value of Pi Raise a number to the specified exponent Convert degrees to radians Generates a random number between 0 and 1 Rounds to the nearest integer value Rounds to a certain precision Square root Truncate (toward zero) Truncate to specified number of decimal places

Finally, take a look at PostgreSQL's trigonometric functions in Table 7.4.

Table 7.4. Trigonometric Functions

Function	Description
acos(x)	inverse cosine
asin(x)	inverse sine
atan(x)	inverse tangent
atan2(x, y)	inverse tangent of y/x
cos(x)	cosine
cot(x)	cotangent
sin(x)	sine
tan(x)	tangent