# Documentation

This version of the OpenSearch documentation is no longer maintained. For the latest version, see the current documentation. For information about OpenSearch version maintenance, see Release Schedule and Maintenance Policy.

# Functions

You must enable fielddata in the document mapping for most string functions to work properly.

The specification shows the return type of the function with a generic type `T` as the argument. For example, `abs(number T) -> T` means that the function `abs` accepts a numerical argument of type `T`, which could be any sub-type of the `number` type, and it returns the actual type of `T` as the return type.

The SQL plugin supports the following functions.

## Mathematical

Function Specification Example
abs `abs(number T) -> T` `SELECT abs(0.5) FROM my-index LIMIT 1`
add `add(number T, number) -> T` `SELECT add(1, 5) FROM my-index LIMIT 1`
cbrt `cbrt(number T) -> T` `SELECT cbrt(0.5) FROM my-index LIMIT 1`
ceil `ceil(number T) -> T` `SELECT ceil(0.5) FROM my-index LIMIT 1`
conv `conv(string T, int a, int b) -> T` `SELECT CONV('12', 10, 16), CONV('2C', 16, 10), CONV(12, 10, 2), CONV(1111, 2, 10) FROM my-index LIMIT 1`
crc32 `crc32(string T) -> T` `SELECT crc32('MySQL') FROM my-index LIMIT 1`
divide `divide(number T, number) -> T` `SELECT divide(1, 0.5) FROM my-index LIMIT 1`
e `e() -> double` `SELECT e() FROM my-index LIMIT 1`
exp `exp(number T) -> T` `SELECT exp(0.5) FROM my-index LIMIT 1`
expm1 `expm1(number T) -> T` `SELECT expm1(0.5) FROM my-index LIMIT 1`
floor `floor(number T) -> T` `SELECT floor(0.5) AS Rounded_Down FROM my-index LIMIT 1`
ln `ln(number T) -> double` `SELECT ln(10) FROM my-index LIMIT 1`
log `log(number T) -> double` or `log(number T, number) -> double` `SELECT log(10) FROM my-index LIMIT 1`
log2 `log2(number T) -> double` `SELECT log2(10) FROM my-index LIMIT 1`
log10 `log10(number T) -> double` `SELECT log10(10) FROM my-index LIMIT 1`
mod `mod(number T, number) -> T` `SELECT modulus(2, 3) FROM my-index LIMIT 1`
multiply `multiply(number T, number) -> number` `SELECT multiply(2, 3) FROM my-index LIMIT 1`
pi `pi() -> double` `SELECT pi() FROM my-index LIMIT 1`
pow `pow(number T) -> T` or `pow(number T, number) -> T` `SELECT pow(2, 3) FROM my-index LIMIT 1`
power `power(number T) -> T` or `power(number T, number) -> T` `SELECT power(2, 3) FROM my-index LIMIT 1`
rand `rand() -> number` or `rand(number T) -> T` `SELECT rand(0.5) FROM my-index LIMIT 1`
rint `rint(number T) -> T` `SELECT rint(1.5) FROM my-index LIMIT 1`
round `round(number T) -> T` `SELECT round(1.5) FROM my-index LIMIT 1`
sign `sign(number T) -> T` `SELECT sign(1.5) FROM my-index LIMIT 1`
signum `signum(number T) -> T` `SELECT signum(0.5) FROM my-index LIMIT 1`
sqrt `sqrt(number T) -> T` `SELECT sqrt(0.5) FROM my-index LIMIT 1`
strcmp `strcmp(string T, string T) -> T` `SELECT strcmp('hello', 'hello') FROM my-index LIMIT 1`
subtract `subtract(number T, number) -> T` `SELECT subtract(3, 2) FROM my-index LIMIT 1`
truncate `truncate(number T, number T) -> T` `SELECT truncate(56.78, 1) FROM my-index LIMIT 1`
/ `number [op] number -> number` `SELECT 1 / 100 FROM my-index LIMIT 1`
% `number [op] number -> number` `SELECT 1 % 100 FROM my-index LIMIT 1`

## Trigonometric

Function Specification Example
acos `acos(number T) -> double` `SELECT acos(0.5) FROM my-index LIMIT 1`
asin `asin(number T) -> double` `SELECT asin(0.5) FROM my-index LIMIT 1`
atan `atan(number T) -> double` `SELECT atan(0.5) FROM my-index LIMIT 1`
atan2 `atan2(number T, number) -> double` `SELECT atan2(1, 0.5) FROM my-index LIMIT 1`
cos `cos(number T) -> double` `SELECT cos(0.5) FROM my-index LIMIT 1`
cosh `cosh(number T) -> double` `SELECT cosh(0.5) FROM my-index LIMIT 1`
cot `cot(number T) -> double` `SELECT cot(0.5) FROM my-index LIMIT 1`
degrees `degrees(number T) -> double` `SELECT degrees(0.5) FROM my-index LIMIT 1`
radians `radians(number T) -> double` `SELECT radians(0.5) FROM my-index LIMIT 1`
sin `sin(number T) -> double` `SELECT sin(0.5) FROM my-index LIMIT 1`
sinh `sinh(number T) -> double` `SELECT sinh(0.5) FROM my-index LIMIT 1`
tan `tan(number T) -> double` `SELECT tan(0.5) FROM my-index LIMIT 1`

## Date and time

Function Specification Example
adddate `adddate(date, INTERVAL expr unit) -> date` `SELECT adddate(date('2020-08-26'), INTERVAL 1 hour) FROM my-index LIMIT 1`
curdate `curdate() -> date` `SELECT curdate() FROM my-index LIMIT 1`
date `date(date) -> date` `SELECT date() FROM my-index LIMIT 1`
date_format `date_format(date, string) -> string` or `date_format(date, string, string) -> string` `SELECT date_format(date, 'Y') FROM my-index LIMIT 1`
date_sub `date_sub(date, INTERVAL expr unit) -> date` `SELECT date_sub(date('2008-01-02'), INTERVAL 31 day) FROM my-index LIMIT 1`
dayofmonth `dayofmonth(date) -> integer` `SELECT dayofmonth(date) FROM my-index LIMIT 1`
dayname `dayname(date) -> string` `SELECT dayname(date('2020-08-26')) FROM my-index LIMIT 1`
dayofyear `dayofyear(date) -> integer` `SELECT dayofyear(date('2020-08-26')) FROM my-index LIMIT 1`
dayofweek `dayofweek(date) -> integer` `SELECT dayofweek(date('2020-08-26')) FROM my-index LIMIT 1`
from_days `from_days(N) -> integer` `SELECT from_days(733687) FROM my-index LIMIT 1`
hour `hour(time) -> integer` `SELECT hour((time '01:02:03')) FROM my-index LIMIT 1`
maketime `maketime(integer, integer, integer) -> date` `SELECT maketime(1, 2, 3) FROM my-index LIMIT 1`
microsecond `microsecond(expr) -> integer` `SELECT microsecond((time '01:02:03.123456')) FROM my-index LIMIT 1`
minute `minute(expr) -> integer` `SELECT minute((time '01:02:03')) FROM my-index LIMIT 1`
month `month(date) -> integer` `SELECT month(date) FROM my-index`
monthname `monthname(date) -> string` `SELECT monthname(date) FROM my-index`
now `now() -> date` `SELECT now() FROM my-index LIMIT 1`
quarter `quarter(date) -> integer` `SELECT quarter(date('2020-08-26')) FROM my-index LIMIT 1`
second `second(time) -> integer` `SELECT second((time '01:02:03')) FROM my-index LIMIT 1`
subdate `subdate(date, INTERVAL expr unit) -> date, datetime` `SELECT subdate(date('2008-01-02'), INTERVAL 31 day) FROM my-index LIMIT 1`
time `time(expr) -> time` `SELECT time('13:49:00') FROM my-index LIMIT 1`
time_to_sec `time_to_sec(time) -> long` `SELECT time_to_sec(time '22:23:00') FROM my-index LIMIT 1`
timestamp `timestamp(date) -> date` `SELECT timestamp(date) FROM my-index LIMIT 1`
to_days `to_days(date) -> long` `SELECT to_days(date '2008-10-07') FROM my-index LIMIT 1`
week `week(date[mode]) -> integer` `SELECT week(date('2008-02-20')) FROM my-index LIMIT 1`
year `year(date) -> integer` `SELECT year(date) FROM my-index LIMIT 1`

## String

Function Specification Example
ascii `ascii(string T) -> integer` `SELECT ascii(name.keyword) FROM my-index LIMIT 1`
concat `concat(str1, str2) -> string` `SELECT concat('hello', 'world') FROM my-index LIMIT 1`
concat_ws `concat_ws(separator, string, string…) -> string` `SELECT concat_ws("-", "Tutorial", "is", "fun!") FROM my-index LIMIT 1`
left `left(string T, integer) -> T` `SELECT left('hello', 2) FROM my-index LIMIT 1`
length `length(string) -> integer` `SELECT length('hello') FROM my-index LIMIT 1`
locate `locate(string, string, integer) -> integer` or `locate(string, string) -> INTEGER` `SELECT locate('o', 'hello') FROM my-index LIMIT 1`, `SELECT locate('l', 'hello', 3) FROM my-index LIMIT 1`
replace `replace(string T, string, string) -> T` `SELECT replace('hello', 'l', 'x') FROM my-index LIMIT 1`
right `right(string T, integer) -> T` `SELECT right('hello', 1) FROM my-index LIMIT 1`
rtrim `rtrim(string T) -> T` `SELECT rtrim(name.keyword) FROM my-index LIMIT 1`
substring `substring(string T, integer, integer) -> T` `SELECT substring(name.keyword, 2,5) FROM my-index LIMIT 1`
trim `trim(string T) -> T` `SELECT trim(' hello') FROM my-index LIMIT 1`
upper `upper(string T) -> T` `SELECT upper('helloworld') FROM my-index LIMIT 1`

## Aggregate

Function Specification Example
avg `avg(number T) -> T` `SELECT avg(2, 3) FROM my-index LIMIT 1`
count `count(number T) -> T` `SELECT count(date) FROM my-index LIMIT 1`
min `min(number T, number) -> T` `SELECT min(2, 3) FROM my-index LIMIT 1`
show `show(string T) -> T` `SHOW TABLES LIKE my-index`

if `if(boolean, es_type, es_type) -> es_type` `SELECT if(false, 0, 1) FROM my-index LIMIT 1`, `SELECT if(true, 0, 1) FROM my-index LIMIT 1`
ifnull `ifnull(es_type, es_type) -> es_type` `SELECT ifnull('hello', 1) FROM my-index LIMIT 1`, `SELECT ifnull(null, 1) FROM my-index LIMIT 1`
isnull `isnull(es_type) -> integer` `SELECT isnull(null) FROM my-index LIMIT 1`, `SELECT isnull(1) FROM my-index LIMIT 1`