Mathematical operators are provided for many PostgreSQL™ types. For types without standard mathematical conventions (e.g., date/time types) we describe the actual behavior in subsequent sections.
Table 9.2, “Mathematical Operators” shows the available mathematical operators.
Table 9.2. Mathematical Operators
Operator | Description | Example | Result |
---|---|---|---|
+ | addition | 2 + 3 | 5 |
- | subtraction | 2 - 3 | -1 |
* | multiplication | 2 * 3 | 6 |
/ | division (integer division truncates the result) | 4 / 2 | 2 |
% | modulo (remainder) | 5 % 4 | 1 |
^ | exponentiation | 2.0 ^ 3.0 | 8 |
|/ | square root | |/ 25.0 | 5 |
||/ | cube root | ||/ 27.0 | 3 |
! | factorial | 5 ! | 120 |
!! | factorial (prefix operator) | !! 5 | 120 |
@ | absolute value | @ -5.0 | 5 |
& | bitwise AND | 91 & 15 | 11 |
| | bitwise OR | 32 | 3 | 35 |
# | bitwise XOR | 17 # 5 | 20 |
~ | bitwise NOT | ~1 | -2 |
<< | bitwise shift left | 1 << 4 | 16 |
>> | bitwise shift right | 8 >> 2 | 2 |
The bitwise operators work only on integral data types, whereas the others are available for all numeric data types. The bitwise operators are also available for the bit string types bit and bit varying, as shown in Table 9.11, “Bit String Operators”.
Table 9.3, “Mathematical Functions” shows the available
mathematical functions. In the table, dp
indicates double precision. Many of these functions
are provided in multiple forms with different argument types.
Except where noted, any given form of a function returns the same
data type as its argument.
The functions working with double precision data are mostly
implemented on top of the host system's C library; accuracy and behavior in
boundary cases can therefore vary depending on the host system.
Table 9.3. Mathematical Functions
Table 9.4, “Random Functions” shows functions for generating random numbers.
The characteristics of the values returned by
depend
on the system implementation. It is not suitable for cryptographic
applications; see pgcrypto module for an alternative.
random()
Finally, Table 9.5, “Trigonometric Functions” shows the
available trigonometric functions. All trigonometric functions
take arguments and return values of type double
precision. Trigonometric functions arguments are expressed
in radians. Inverse functions return values are expressed in
radians. See unit transformation functions
and
radians()
above.
degrees()