| PostgreSQL 9.5.25 Documentation | |||
|---|---|---|---|
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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 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 (associates left to right) | 2.0 ^ 3.0 | 8 |
| |/ | square root | |/ 25.0 | 5 |
| ||/ | cube root | ||/ 27.0 | 3 |
| ! | factorial (deprecated, use factorial() instead) |
5 ! | 120 |
| !! | factorial as a prefix operator (deprecated, use factorial() instead) |
!! 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 and are also available for the bit string types bit and bit varying, as shown in Table 9-11.
Table 9-3 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
| Function | Return Type | Description | Example | Result |
|---|---|---|---|---|
abs(x) |
(same as input) | absolute value | abs(-17.4) | 17.4 |
cbrt(dp) |
dp | cube root | cbrt(27.0) | 3 |
ceil(dp or numeric) |
(same as input) | nearest integer greater than or equal to argument | ceil(-42.8) | -42 |
ceiling(dp or numeric) |
(same as input) | nearest integer greater than or equal to argument (same as ceil) |
ceiling(-95.3) | -95 |
degrees(dp) |
dp | radians to degrees | degrees(0.5) | 28.6478897565412 |
div(y numeric, x numeric) |
numeric | integer quotient of y/x | div(9,4) | 2 |
exp(dp or numeric) |
(same as input) | exponential | exp(1.0) | 2.71828182845905 |
factorial(bigint) |
numeric | factorial | factorial(5) | 120 |
floor(dp or numeric) |
(same as input) | nearest integer less than or equal to argument | floor(-42.8) | -43 |
ln(dp or numeric) |
(same as input) | natural logarithm |