Mathematical Functions and Operators
Numeric Operators
+
Description: Addition
Example:
openGauss=# SELECT 2+3 AS RESULT; result -------- 5 (1 row)
-
Description: Subtraction
Example:
openGauss=# SELECT 2-3 AS RESULT; result -------- -1 (1 row)
*
Description: Multiplication
Example:
openGauss=# SELECT 2*3 AS RESULT; result -------- 6 (1 row)
/
Description: Division (The result is not rounded.)
Example:
openGauss=# SELECT 4/2 AS RESULT; result -------- 2 (1 row)
openGauss=# SELECT 4/3 AS RESULT; result ------------------ 1.33333333333333 (1 row)
+/-
Description: Positive/Negative
Example:
openGauss=# SELECT -2 AS RESULT; result -------- -2 (1 row)
%
Description: Model (to obtain the remainder)
Example:
openGauss=# SELECT 5%4 AS RESULT; result -------- 1 (1 row)
@
Description: Absolute value
Example:
openGauss=# SELECT @ -5.0 AS RESULT; result -------- 5.0 (1 row)
^
Description: Power (exponent calculation)
Example:
openGauss=# SELECT 2.0^3.0 AS RESULT; result -------------------- 8.0000000000000000 (1 row)
|/
Description: Square root
Example:
openGauss=# SELECT |/ 25.0 AS RESULT; result -------- 5 (1 row)
||/
Description: Cubic root
Example:
openGauss=# SELECT ||/ 27.0 AS RESULT; result -------- 3 (1 row)
!
Description: Factorial
Example:
openGauss=# SELECT 5! AS RESULT; result -------- 120 (1 row)
!!
Description: Factorial (prefix operator)
Example:
openGauss=# SELECT !!5 AS RESULT; result -------- 120 (1 row)
&
Description: Binary AND
Example:
openGauss=# SELECT 91&15 AS RESULT; result -------- 11 (1 row)
|
Description: Binary OR
Example:
openGauss=# SELECT 32|3 AS RESULT; result -------- 35 (1 row)
#
Description: Binary XOR
Example:
openGauss=# SELECT 17#5 AS RESULT; result -------- 20 (1 row)
~
Description: Binary NOT
Example:
openGauss=# SELECT ~1 AS RESULT; result -------- -2 (1 row)
«
Description: Binary shift left
Example:
openGauss=# SELECT 1<<4 AS RESULT; result -------- 16 (1 row)
>>
Description: Binary shift right
Example:
openGauss=# SELECT 8>>2 AS RESULT; result -------- 2 (1 row)
Numeric Operation Functions
abs(x)
Description: Absolute value
Return type: same as the input
Example:
openGauss=# SELECT abs(-17.4); abs ------ 17.4 (1 row)
acos(x)
Description: Arc cosine
Return type: double precision
Example:
openGauss=# SELECT acos(-1); acos ------------------ 3.14159265358979 (1 row)
asin(x)
Description: Arc sine
Return type: double precision
Example:
openGauss=# SELECT asin(0.5); asin ------------------ .523598775598299 (1 row)
atan(x)
Description: Arc tangent
Return type: double precision
Example:
openGauss=# SELECT atan(1); atan ------------------ .785398163397448 (1 row)
atan2(y, x)
Description: Arc tangent of y/x
Return type: double precision
Example:
openGauss=# SELECT atan2(2, 1); atan2 ------------------ 1.10714871779409 (1 row)
bitand(integer, integer)
Description: Performs an AND (&) operation on two integers.
Return type: bigint
Example:
openGauss=# SELECT bitand(127, 63); bitand -------- 63 (1 row)
cbrt(dp)
Description: Cubic root
Return type: double precision
Example:
openGauss=# SELECT cbrt(27.0); cbrt ------ 3 (1 row)
ceil(x)
Description: Minimum integer greater than or equal to the parameter
Return type: integer
Example:
openGauss=# SELECT ceil(-42.8); ceil ------ -42 (1 row)
ceiling(dp or numeric)
Description: Minimum integer (alias of ceil) greater than or equal to the parameter
Return type: dp or numeric. If implicit type conversion is not considered, the return type is the same as the input type.
Example:
openGauss=# SELECT ceiling(-95.3); ceiling --------- -95 (1 row)
cos(x)
Description: Cosine
Return type: double precision
Example:
openGauss=# SELECT cos(-3.1415927); cos ------------------- -.999999999999999 (1 row)
cot(x)
Description: Cotangent
Return type: double precision
Example:
openGauss=# SELECT cot(1); cot ------------------ .642092615934331 (1 row)
degrees(dp)
Description: Converts radians to angles.
Return type: double precision
Example:
openGauss=# SELECT degrees(0.5); degrees ------------------ 28.6478897565412 (1 row)
div(y numeric, x numeric)
Description: Integer part of y/x
Return type: numeric
Example:
openGauss=# SELECT div(9,4); div ----- 2 (1 row)
exp(x)
Description: Natural exponent
Return type: dp or numeric. If implicit type conversion is not considered, the return type is the same as the input type.
Example:
openGauss=# SELECT exp(1.0); exp -------------------- 2.7182818284590452 (1 row)
floor(x)
Description: Maximum integer not larger than the parameter
Return type: same as the input
Example:
openGauss=# SELECT floor(-42.8); floor ------- -43 (1 row)
int1(in)
Description: Converts the input text parameter to a value of the int1 type and returns the value.
Return type: int1
Example:
openGauss=# select int1('123'); int1 ------ 123 (1 row) openGauss=# select int1('a'); int1 ------ 0 (1 row)
int2(in)
Description: Converts the input parameter to a value of the int2 type and returns the value.
The supported input parameter types include float4, float8, int16, numeric, and text.
Return type: int2
Example:
openGauss=# select int2('1234'); int2 ------ 1234 (1 row) openGauss=# select int2(25.3); int2 ------ 25 (1 row)
int4(in)
Description: Converts the input parameter to a value of the int4 type and returns the value.
The supported input parameter types include bit, boolean, char, double precision, int16, numeric, real, smallint and text
Return type: int4
Example:
openGauss=# select int4('789'); int4 ------ 789 (1 row) openGauss=# select int4(99.9); int4 ------ 99 (1 row)
float4(in)
Description: Converts the input parameter to a value of the float4 type and returns the value. The supported input parameter types include bigint, duoble precision, int16, integer, numeric, smallint, and text.
Return type: float4
Example:
openGauss=# select float4('789'); float4 -------- 789 (1 row) openGauss=# select float4(99.9); float4 -------- 99.9 (1 row)
float8(in)
Description: Converts the input parameter to a value of the float8 type and returns the value. The supported input parameter types include bigint, int16, integer, numeric, real, smallint, and text.
Return type: float8
Example:
openGauss=# select float8('789'); float8 -------- 789 (1 row) openGauss=# select float8(99.9); float8 -------- 99.9 (1 row)
int16(in)
Description: Converts the input parameter to a value of the int16 type and returns the value. The supported input parameter types include bigint, boolean, double precision, integer, numeric, oid, real, smallint, and tinyint.
Return type: int16
Example:
openGauss=# select int16('789'); int16 -------- 789 (1 row) openGauss=# select int16(99.9); int16 -------- 99 (1 row)
numeric(in)
Description: Converts the input parameter to a value of the numeric type and returns the value. The supported input parameter types include bigint, boolean, double precision, int16, integer, money, real, and smallint.
Return type: numeric
Example:
openGauss=# select "numeric"('789'); numeric --------- 789 (1 row) openGauss=# select "numeric"(99.9); numeric --------- 99.9 (1 row)
oid(in)
Description: Converts the input parameter to a value of the oid type and returns the value. The supported input parameter types include bigint and int16.
Return type: oid
radians(dp)
Description: Converts angles to radians.
Return type: double precision
Example:
openGauss=# SELECT radians(45.0); radians ------------------ .785398163397448 (1 row)
random()
Description: Random number between 0.0 and 1.0
Return type: double precision
Example:
openGauss=# SELECT random(); random ------------------ .824823560658842 (1 row)
multiply(x double precision or text, y double precision or text)
Description: Product of x and y.
Return type: double precision
Example:
openGauss=# SELECT multiply(9.0, '3.0'); multiply ------------------- 27 (1 row) openGauss=# SELECT multiply('9.0', 3.0); multiply ------------------- 27 (1 row)
ln(x)
Description: Natural logarithm
Return type: dp or numeric. If implicit type conversion is not considered, the return type is the same as the input type.
Example:
openGauss=# SELECT ln(2.0); ln ------------------- .6931471805599453 (1 row)
log(x)
Description: Logarithm with 10 as the base
Return type: same as the input
Example:
openGauss=# SELECT log(100.0); log -------------------- 2.0000000000000000 (1 row)
log(b numeric, x numeric)
Description: Logarithm with b as the base
Return type: numeric
Example:
openGauss=# SELECT log(2.0, 64.0); log -------------------- 6.0000000000000000 (1 row)
mod(x,y)
Description: Remainder of x/y (model) If x equals to 0, 0 is returned.
Return type: same as the parameter type
Example:
openGauss=# SELECT mod(9,4); mod ----- 1 (1 row)
openGauss=# SELECT mod(9,0); mod ----- 9 (1 row)
pi()
Description: π constant value
Return type: double precision
Example:
openGauss=# SELECT pi(); pi ------------------ 3.14159265358979 (1 row)
power(a double precision, b double precision)
Description: b power of a
Return type: double precision
Example:
openGauss=# SELECT power(9.0, 3.0); power ---------------------- 729.0000000000000000 (1 row)
round(x)
Description: Integer closest to the input parameter
Return type: same as the input
Example:
openGauss=# SELECT round(42.4); round ------- 42 (1 row) openGauss=# SELECT round(42.6); round ------- 43 (1 row)
round(v numeric, s int)
Description: s digits are kept after the decimal point.
Return type: numeric
Example:
openGauss=# SELECT round(42.4382, 2); round ------- 42.44 (1 row)
setseed(dp)
Description: Sets seed for the following random() invoking (between –1.0 and 1.0, inclusive).
Return type: void
Example:
openGauss=# SELECT setseed(0.54823); setseed --------- (1 row)
sign(x)
Description: Returns symbols of this parameter.
Return type: –1 indicates minus. 0 indicates 0, and 1 indicates positive numbers.
Example:
openGauss=# SELECT sign(-8.4); sign ------ -1 (1 row)
sin(x)
Description: Sine
Return type: double precision
Example:
openGauss=# SELECT sin(1.57079); sin ------------------ .999999999979986 (1 row)
sqrt(x)
Description: Square root
Return type: dp or numeric. If implicit type conversion is not considered, the return type is the same as the input type.
Example:
openGauss=# SELECT sqrt(2.0); sqrt ------------------- 1.414213562373095 (1 row)
tan(x)
Description: Tangent
Return type: double precision
Example:
openGauss=# SELECT tan(20); tan ------------------ 2.23716094422474 (1 row)
trunc(x)
Description: Truncates (the integral part).
Return type: same as the input
Example:
openGauss=# SELECT trunc(42.8); trunc ------- 42 (1 row)
trunc(v numeric, s int)
Description: Truncates a number with s digits after the decimal point.
Return type: numeric
Example:
openGauss=# SELECT trunc(42.4382, 2); trunc ------- 42.43 (1 row)
smgrne(a smgr, b smgr)
Description: Compares two integers of the smgr type to check whether they are different.
Return type: Boolean
smgreq(a smgr, b smgr)
Description: Compares two integers of the smgr type to check whether they are equivalent.
Return type: Boolean
int1abs
Description: Returns the absolute value of data of the uint8 type.
Parameter: tinyint
Return type: tinyint
int1and
Description: Returns the bitwise AND result of two data records of the uint8 type.
Parameter: tinyint, tinyint
Return type: tinyint
int1cmp
Description: Returns the comparison result of two data records of the uint8 type. If the value of the first parameter is greater, 1 is returned. If the value of the second parameter is greater, –1 is returned. If they are the same, 0 is returned.
Parameter: tinyint, tinyint
Return type: integer
int1div
Description: Returns the result of dividing two data records of the uint8 type. The result is of the float8 type.
Parameter: tinyint, tinyint
Return type: tinyint
int1eq
Description: Compares two pieces of data of the uint8 type to check whether they are the same.
Parameter: tinyint, tinyint
Return type: Boolean
int1ge
Description: Determines whether the value of the first parameter is greater than or equal to the value of the second parameter in two data records of the uint8 type.
Parameter: tinyint, tinyint
Return type: Boolean
int1gt
Description: Performs a greater-than operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: Boolean
int1larger
Description: Returns the maximum value of an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
int1le
Description: Performs a less-than or an equal-to operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: Boolean
int1lt
Description: Performs a less-than operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: Boolean
int1smaller
Description: Calculates the minimum value of an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
int1inc
Description: Unsigned 1-byte integer plus 1.
Parameter: tinyint
Return type: tinyint
int1mi
Description: Performs a minus operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
int1mod
Description: Performs a reminder operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
int1mul
Description: Performs a multiplication operation on unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
int1ne
Description: Performs a not-equal-to operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: Boolean
int1pl
Description: Performs an addition operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
int1um
Description: Returns an unsigned 2-byte integer after subtracting the opposite number from the unsigned 1-byte integer.
Parameter: tinyint
Return type: smallint
int1xor
Description: Performs an exclusive OR operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
cash_div_int1
Description: Performs a division operation on the money type.
Parameter: money, tinyint
Return type: money
cash_mul_int1
Description: Performs a multiplication operation on the money type.
Parameter: money, tinyint
Return type: money
int1not
Description: Reverts binary bits of an unsigned 1-byte integer.
Parameter: tinyint
Return type: tinyint
int1or
Description: Performs an OR operation on an unsigned 1-byte integer.
Parameter: tinyint, tinyint
Return type: tinyint
int1shl
Description: Shifts an unsigned 1-byte integer leftwards by a specified number of bits.
Parameter: tinyint, integer
Return type: tinyint
width_bucket(op numeric, b1 numeric, b2 numeric, count int)
Description: Returns a bucket to which the operand will be assigned in an equi-depth histogram with count buckets, ranging from b1 to b2.
Return type: int
Example:
openGauss=# SELECT width_bucket(5.35, 0.024, 10.06, 5); width_bucket -------------- 3 (1 row)
width_bucket(op dp, b1 dp, b2 dp, count int)
Description: Returns a bucket to which the operand will be assigned in an equi-depth histogram with count buckets, ranging from b1 to b2.
Return type: int
Example:
openGauss=# SELECT width_bucket(5.35, 0.024, 10.06, 5); width_bucket -------------- 3 (1 row)