---
id: sql-functions
title: "All Druid SQL functions"
sidebar_label: "All functions"
---

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> Apache Druid supports two query languages: Druid SQL and [native queries](querying.md).
> This document describes the SQL language.


This page provides a reference of all Druid SQL functions in alphabetical order.
Click the linked function type for documentation on a particular function.

## ABS

`ABS(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the absolute value of a numeric expression.

## ACOS

`ACOS(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the arc cosine of a numeric expression.

## ANY_VALUE

`ANY_VALUE(<NUMERIC>)`

`ANY_VALUE(<BOOLEAN>)`

`ANY_VALUE(<CHARACTER>, <NUMERIC>)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns any value of the specified expression.

## APPROX_COUNT_DISTINCT

`APPROX_COUNT_DISTINCT(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Counts distinct values of a regular column or a prebuilt sketch column.

`APPROX_COUNT_DISTINCT_BUILTIN(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Counts distinct values of a string, numeric, or `hyperUnique` column using Druid's built-in `cardinality` or `hyperUnique` aggregators.

## APPROX_COUNT_DISTINCT_DS_HLL

`APPROX_COUNT_DISTINCT_DS_HLL(expr, [<NUMERIC>, <CHARACTER>])`

**Function type:** [Aggregation](sql-aggregations.md)

Counts distinct values of an HLL sketch column or a regular column.

## APPROX_COUNT_DISTINCT_DS_THETA

`APPROX_COUNT_DISTINCT_DS_THETA(expr, [<NUMERIC>])`

**Function type:** [Aggregation](sql-aggregations.md)

Counts distinct values of a Theta sketch column or a regular column.

## APPROX_QUANTILE

`APPROX_QUANTILE(expr, <NUMERIC>, [<NUMERIC>])`

**Function type:** [Aggregation](sql-aggregations.md)

Deprecated in favor of `APPROX_QUANTILE_DS`.

## APPROX_QUANTILE_DS

`APPROX_QUANTILE_DS(expr, <NUMERIC>, [<NUMERIC>])`

**Function type:** [Aggregation](sql-aggregations.md)

Computes approximate quantiles on a Quantiles sketch column or a regular numeric column.

## APPROX_QUANTILE_FIXED_BUCKETS

`APPROX_QUANTILE_FIXED_BUCKETS(expr, <NUMERIC>, <NUMERIC>, <NUMERIC>, <NUMERIC>, [<CHARACTER>])`

**Function type:** [Aggregation](sql-aggregations.md)

Computes approximate quantiles on fixed buckets histogram column or a regular numeric column.

## ARRAY[]

`ARRAY[expr1, expr2, ...]`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Constructs a SQL ARRAY literal from the expression arguments. The arguments must be of the same type.

## ARRAY_AGG

`ARRAY_AGG([DISTINCT] expr, [<NUMERIC>])`

**Function type:** [Aggregation](sql-aggregations.md)

Returns an array of all values of the specified expression.

## ARRAY_CONCAT_AGG

`ARRAY_CONCAT_AGG([DISTINCT] expr, [<NUMERIC>])`

**Function type:** [Aggregation](sql-aggregations.md)

Concatenates array inputs into a single array.

## ASIN

`ASIN(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the arc sine of a numeric expression.

## ATAN

`ATAN(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the arc tangent of a numeric expression.

## ATAN2

`ATAN2(<NUMERIC>, <NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the arc tangent of the two arguments.

## AVG

`AVG(<NUMERIC>)`

**Function type:** [Aggregation](sql-aggregations.md)

Calculates the average of a set of values.

## BIT_AND

`BIT_AND(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Performs a bitwise AND operation on all input values.

## BIT_OR

`BIT_OR(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Performs a bitwise OR operation on all input values.

## BIT_XOR

`BIT_XOR(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Performs a bitwise XOR operation on all input values.

## BITWISE_AND

`BITWISE_AND(expr1, expr2)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns the bitwise AND between the two expressions, that is, `expr1 & expr2`.

## BITWISE_COMPLEMENT

`BITWISE_COMPLEMENT(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns the bitwise NOT for the expression, that is, `~expr`.

## BITWISE_CONVERT_DOUBLE_TO_LONG_BITS

`BITWISE_CONVERT_DOUBLE_TO_LONG_BITS(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Converts the bits of an IEEE 754 floating-point double value to a long.

## BITWISE_CONVERT_LONG_BITS_TO_DOUBLE

`BITWISE_CONVERT_LONG_BITS_TO_DOUBLE(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Converts a long to the IEEE 754 floating-point double specified by the bits stored in the long.

## BITWISE_OR

`BITWISE_OR(expr1, expr2)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns the bitwise OR between the two expressions, that is, `expr1 | expr2`.

## BITWISE_SHIFT_LEFT

`BITWISE_SHIFT_LEFT(expr1, expr2)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns a bitwise left shift of expr1, that is, `expr1 << expr2`.

## BITWISE_SHIFT_RIGHT

`BITWISE_SHIFT_RIGHT(expr1, expr2)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns a bitwise right shift of expr1, that is, `expr1 >> expr2`.

## BITWISE_XOR

`BITWISE_XOR(expr1, expr2)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns the bitwise exclusive OR between the two expressions, that is, `expr1 ^ expr2`.

## BLOOM_FILTER

`BLOOM_FILTER(expr, <NUMERIC>)`

**Function type:** [Aggregation](sql-aggregations.md)

Computes a Bloom filter from values produced by the specified expression.

## BLOOM_FILTER_TEST

`BLOOM_FILTER_TEST(expr, <STRING>)`

**Function type:** [Scalar, other](sql-scalar.md#other-scalar-functions)

Returns true if the expression is contained in a Base64-serialized Bloom filter.

## BTRIM

`BTRIM(<CHARACTER>, [<CHARACTER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Trims characters from both the leading and trailing ends of an expression.

## CASE

`CASE expr WHEN value1 THEN result1 \[ WHEN value2 THEN result2 ... \] \[ ELSE resultN \] END`

**Function type:** [Scalar, other](sql-scalar.md#other-scalar-functions)

Returns a result based on a given condition.

## CAST

`CAST(value AS TYPE)`

**Function type:** [Scalar, other](sql-scalar.md#other-scalar-functions)

Converts a value into the specified data type.

## CEIL (date and time)

`CEIL(<TIMESTAMP> TO <TIME_UNIT>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Rounds up a timestamp by a given time unit.

## CEIL (numeric)

`CEIL(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the smallest integer value greater than or equal to the numeric expression.

## CHAR_LENGTH

`CHAR_LENGTH(expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Alias for [`LENGTH`](#length).

## CHARACTER_LENGTH

`CHARACTER_LENGTH(expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Alias for [`LENGTH`](#length).

## COALESCE

`COALESCE(expr, expr, ...)`

**Function type:** [Scalar, other](sql-scalar.md#other-scalar-functions)

Returns the first non-null value.

## CONCAT

`CONCAT(expr, expr...)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Concatenates a list of expressions.

## CONTAINS_STRING

`CONTAINS_STRING(<CHARACTER>, <CHARACTER>)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Finds whether a string is in a given expression, case-sensitive.

## COS

`COS(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the trigonometric cosine of an angle expressed in radians.

## COT

`COT(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the trigonometric cotangent of an angle expressed in radians.

## COUNT

`COUNT([DISTINCT] expr)`

`COUNT(*)`

**Function type:** [Aggregation](sql-aggregations.md)

Counts the number of rows.

## CURRENT_DATE

`CURRENT_DATE`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Returns the current date in the connection's time zone.

## CURRENT_TIMESTAMP

`CURRENT_TIMESTAMP`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Returns the current timestamp in the connection's time zone.

## DATE_TRUNC

`DATE_TRUNC(<CHARACTER>, <TIMESTAMP>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Rounds down a timestamp by a given time unit.

## DEGREES

`DEGREES(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Converts an angle from radians to degrees.

## DIV

`DIV(x, y)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns the result of integer division of `x` by `y`.

## DS_CDF

`DS_CDF(expr, splitPoint0, splitPoint1, ...)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a string representing an approximation to the Cumulative Distribution Function given the specified bin definition.

## DS_GET_QUANTILE

`DS_GET_QUANTILE(expr, fraction)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns the quantile estimate corresponding to `fraction` from a quantiles sketch.

## DS_GET_QUANTILES

`DS_GET_QUANTILES(expr, fraction0, fraction1, ...)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a string representing an array of quantile estimates corresponding to a list of fractions from a quantiles sketch.

## DS_HISTOGRAM

`DS_HISTOGRAM(expr, splitPoint0, splitPoint1, ...)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a string representing an approximation to the histogram given the specified bin definition.


## DS_HLL

`DS_HLL(expr, [lgK, tgtHllType])`

**Function type:** [Aggregation](sql-aggregations.md)

Creates an HLL sketch on a column containing HLL sketches or a regular column.

## DS_QUANTILE_SUMMARY

`DS_QUANTILE_SUMMARY(expr)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a string summary of a quantiles sketch.

## DS_QUANTILES_SKETCH

`DS_QUANTILES_SKETCH(expr, [k])`

**Function type:** [Aggregation](sql-aggregations.md)

Creates a Quantiles sketch on a column containing Quantiles sketches or a regular column.

## DS_RANK

`DS_RANK(expr, value)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns an approximate rank between 0 and 1 of a given value, in which the rank signifies the fraction of the distribution less than the given value.

## DS_THETA

`DS_THETA(expr, [size])`

**Function type:** [Aggregation](sql-aggregations.md)

Creates a Theta sketch on a column containing Theta sketches or a regular column.

## EARLIEST

`EARLIEST(expr)`

`EARLIEST(expr, maxBytesPerString)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns the value of a numeric or string expression corresponding to the earliest `__time` value.

## EARLIEST_BY

`EARLIEST_BY(expr, timestampExpr)`

`EARLIEST_BY(expr, timestampExpr, maxBytesPerString)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns the value of a numeric or string expression corresponding to the earliest time value from `timestampExpr`.

## EXP

`EXP(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates _e_ raised to the power of the numeric expression.

## EXTRACT

`EXTRACT(<TIME_UNIT> FROM <TIMESTAMP>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Extracts the value of some unit of the timestamp, optionally from a certain time zone, and returns the number.

## FLOOR (date and time)

`FLOOR(<TIMESTAMP> TO <TIME_UNIT>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Rounds down a timestamp by a given time unit.

## FLOOR (numeric)

`FLOOR(<NUMERIC>)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the largest integer value less than or equal to the numeric expression.

## GREATEST

`GREATEST([expr1, ...])`

**Function type:** [Scalar, reduction](sql-scalar.md#reduction-functions)

Returns the maximum value from the provided arguments.

## GROUPING

`GROUPING(expr, expr...)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns a number for each output row of a groupBy query, indicating whether the specified dimension is included for that row.

## HLL_SKETCH_ESTIMATE

`HLL_SKETCH_ESTIMATE(expr, [round])`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns the distinct count estimate from an HLL sketch.

## HLL_SKETCH_ESTIMATE_WITH_ERROR_BOUNDS

`HLL_SKETCH_ESTIMATE_WITH_ERROR_BOUNDS(expr, [numStdDev])`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns the distinct count estimate and error bounds from an HLL sketch.

## HLL_SKETCH_TO_STRING

`HLL_SKETCH_TO_STRING(expr)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a human-readable string representation of an HLL sketch.

## HLL_SKETCH_UNION

`HLL_SKETCH_UNION([lgK, tgtHllType], expr0, expr1, ...)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a union of HLL sketches.

## HUMAN_READABLE_BINARY_BYTE_FORMAT

`HUMAN_READABLE_BINARY_BYTE_FORMAT(value[, precision])`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Converts an integer byte size into human-readable IEC format.

## HUMAN_READABLE_DECIMAL_BYTE_FORMAT

`HUMAN_READABLE_DECIMAL_BYTE_FORMAT(value[, precision])`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Converts a byte size into human-readable SI format.

## HUMAN_READABLE_DECIMAL_FORMAT

`HUMAN_READABLE_DECIMAL_FORMAT(value[, precision])`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Converts a byte size into human-readable SI format with single-character units.

## ICONTAINS_STRING

`ICONTAINS_STRING(<expr>, str)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Finds whether a string is in a given expression, case-insensitive.

## IPV4_MATCH

`IPV4_MATCH(address, subnet)`

**Function type:** [Scalar, IP address](sql-scalar.md#ip-address-functions)

Returns true if the `address` belongs to the `subnet` literal, else false.

## IPV4_PARSE

`IPV4_PARSE(address)`

**Function type:** [Scalar, IP address](sql-scalar.md#ip-address-functions)

Parses `address` into an IPv4 address stored as an integer.

## IPV4_STRINGIFY

`IPV4_STRINGIFY(address)`

**Function type:** [Scalar, IP address](sql-scalar.md#ip-address-functions)

Converts `address` into an IPv4 address in dot-decimal notation.

## LATEST

`LATEST(expr)`

`LATEST(expr, maxBytesPerString)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns the value of a numeric or string expression corresponding to the latest `__time` value.

## LATEST_BY

`LATEST_BY(expr, timestampExpr)`

`LATEST_BY(expr, timestampExpr, maxBytesPerString)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns the value of a numeric or string expression corresponding to the latest time value from `timestampExpr`.

## LEAST

`LEAST([expr1, ...])`

**Function type:** [Scalar, reduction](sql-scalar.md#reduction-functions)

Returns the minimum value from the provided arguments.

## LEFT

`LEFT(expr, [length])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the leftmost number of characters from an expression.

## LENGTH

`LENGTH(expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the length of the expression in UTF-16 encoding.

## LN

`LN(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the natural logarithm of the numeric expression.

## LOG10

`LOG10(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the base-10 of the numeric expression.

## LOOKUP

`LOOKUP(<CHARACTER>, <CHARACTER>)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Looks up the expression in a registered query-time lookup table.

## LOWER

`LOWER(expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the expression in lowercase.

## LPAD

`LPAD(<CHARACTER>, <INTEGER>, [<CHARACTER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the leftmost number of characters from an expression, optionally padded with the given characters.

## LTRIM

`LTRIM(<CHARACTER>, [<CHARACTER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Trims characters from the leading end of an expression.

## MAX

`MAX(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns the maximum value of a set of values.

## MILLIS_TO_TIMESTAMP

`MILLIS_TO_TIMESTAMP(millis_expr)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Converts a number of milliseconds since epoch into a timestamp.

## MIN

`MIN(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Returns the minimum value of a set of values.

## MOD

`MOD(x, y)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates x modulo y, or the remainder of x divided by y.

## MV_APPEND

`MV_APPEND(arr1, expr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Adds the expression to the end of the array.

## MV_CONCAT

`MV_CONCAT(arr1, arr2)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Concatenates two arrays.

## MV_CONTAINS

`MV_CONTAINS(arr, expr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns true if the expression is in the array, false otherwise.

## MV_FILTER_NONE

`MV_FILTER_NONE(expr, arr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Filters a multi-value expression to include no values contained in the array.

## MV_FILTER_ONLY

`MV_FILTER_ONLY(expr, arr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Filters a multi-value expression to include only values contained in the array.

## MV_LENGTH

`MV_LENGTH(arr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns the length of an array expression.

## MV_OFFSET

`MV_OFFSET(arr, long)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns the array element at the given zero-based index.

## MV_OFFSET_OF

`MV_OFFSET_OF(arr, expr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns the zero-based index of the first occurrence of a given expression in the array.

## MV_ORDINAL

`MV_ORDINAL(arr, long)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns the array element at the given one-based index.

## MV_ORDINAL_OF

`MV_ORDINAL_OF(arr, expr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns the one-based index of the first occurrence of a given expression.

## MV_OVERLAP

`MV_OVERLAP(arr1, arr2)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns true if the two arrays have any elements in common, false otherwise.

## MV_PREPEND

`MV_PREPEND(expr, arr)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Adds the expression to the beginning of the array.

## MV_SLICE

`MV_SLICE(arr, start, end)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Returns a slice of the array from the zero-based start and end indexes.

## MV_TO_STRING

`MV_TO_STRING(arr, str)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Joins all elements of the array together by the given delimiter.

## NULLIF

`NULLIF(value1, value2)`

**Function type:** [Scalar, other](sql-scalar.md#other-scalar-functions)

Returns NULL if two values are equal, else returns the first value.

## NVL

`NVL(e1, e2)`

**Function type:** [Scalar, other](sql-scalar.md#other-scalar-functions)

Returns `e2` if `e1` is null, else returns `e1`.

## PARSE_LONG

`PARSE_LONG(<CHARACTER>, [<INTEGER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Converts a string into a BIGINT with the given base or into a DECIMAL data type if the base is not specified.

## POSITION

`POSITION(<CHARACTER> IN <CHARACTER> [FROM <INTEGER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the one-based index position of a substring within an expression, optionally starting from a given one-based index.

## POWER

`POWER(expr, power)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates a numerical expression raised to the specified power.

## RADIANS

`RADIANS(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Converts an angle from degrees to radians.

## REGEXP_EXTRACT

`REGEXP_EXTRACT(<CHARACTER>, <CHARACTER>, [<INTEGER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Applies a regular expression to the string expression and returns the _n_th match.

## REGEXP_LIKE

`REGEXP_LIKE(<CHARACTER>, <CHARACTER>)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns true or false signifying whether the regular expression finds a match in the string expression.

## REPEAT

`REPEAT(<CHARACTER>, [<INTEGER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Repeats the string expression an integer number of times.

## REPLACE

`REPLACE(expr, pattern, replacement)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Replaces a pattern with another string in the given expression.

## REVERSE

`REVERSE(expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Reverses the given expression.

## RIGHT

`RIGHT(expr, [length])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the rightmost number of characters from an expression.

## ROUND

`ROUND(expr[, digits])`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the rounded value for a numerical expression.

## RPAD

`RPAD(<CHARACTER>, <INTEGER>, [<CHARACTER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the rightmost number of characters from an expression, optionally padded with the given characters.

## RTRIM

`RTRIM(<CHARACTER>, [<CHARACTER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Trims characters from the trailing end of an expression.

## SAFE_DIVIDE

`SAFE_DIVIDE(x, y)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Returns `x` divided by `y`, guarded on division by 0.

## SIN

`SIN(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the trigonometric sine of an angle expressed in radians.

## SQRT

`SQRT(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the square root of a numeric expression.

## STDDEV

`STDDEV(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Alias for [`STDDEV_SAMP`](#stddev_samp).

## STDDEV_POP

`STDDEV_POP(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Calculates the population standard deviation of a set of values.

## STDDEV_SAMP

`STDDEV_SAMP(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Calculates the sample standard deviation of a set of values.

## STRING_AGG

`STRING_AGG(expr, separator, [size])`

**Function type:** [Aggregation](sql-aggregations.md)

Collects all values of an expression into a single string.

## STRING_FORMAT

`STRING_FORMAT(pattern[, args...])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns a string formatted in accordance to Java's String.format method.

## STRING_TO_MV

`STRING_TO_MV(str1, str2)`

**Function type:** [Multi-value string](sql-multivalue-string-functions.md)

Converts a string into an array, split by the given delimiter.

## STRLEN

`STRLEN(expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Alias for [`LENGTH`](#length).

## STRPOS

`STRPOS(<CHARACTER>, <CHARACTER>)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the one-based index position of a substring within an expression.

## SUBSTR

`SUBSTR(<CHARACTER>, <INTEGER>, [<INTEGER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Alias for [`SUBSTRING`](#substring).

## SUBSTRING

`SUBSTRING(<CHARACTER>, <INTEGER>, [<INTEGER>])`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns a substring of the expression starting at a given one-based index.

## SUM

`SUM(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Calculates the sum of a set of values.

## TAN

`TAN(expr)`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Calculates the trigonometric tangent of an angle expressed in radians.

## TDIGEST_GENERATE_SKETCH

`TDIGEST_GENERATE_SKETCH(expr, [compression])`

**Function type:** [Aggregation](sql-aggregations.md)

Generates a T-digest sketch from values of the specified expression.

## TDIGEST_QUANTILE

`TDIGEST_QUANTILE(expr, quantileFraction, [compression])`

**Function type:** [Aggregation](sql-aggregations.md)

Returns the quantile for the specified fraction from a T-Digest sketch constructed from values of the expression.

## TEXTCAT

`TEXTCAT(<CHARACTER>, <CHARACTER>)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Concatenates two string expressions.

## THETA_SKETCH_ESTIMATE

`THETA_SKETCH_ESTIMATE(expr)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns the distinct count estimate from a Theta sketch.

## THETA_SKETCH_ESTIMATE_WITH_ERROR_BOUNDS

`THETA_SKETCH_ESTIMATE_WITH_ERROR_BOUNDS(expr, errorBoundsStdDev)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns the distinct count estimate and error bounds from a Theta sketch.

## THETA_SKETCH_INTERSECT

`THETA_SKETCH_INTERSECT([size], expr0, expr1, ...)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns an intersection of Theta sketches.

## THETA_SKETCH_NOT

`THETA_SKETCH_NOT([size], expr0, expr1, ...)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a set difference of Theta sketches.

## THETA_SKETCH_UNION

`THETA_SKETCH_UNION([size], expr0, expr1, ...)`

**Function type:** [Scalar, sketch](sql-scalar.md#sketch-functions)

Returns a union of Theta sketches.

## TIME_CEIL

`TIME_CEIL(<TIMESTAMP>, <period>, [<origin>, [<timezone>]])`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Rounds up a timestamp by a given time period, optionally from some reference time or timezone.

## TIME_EXTRACT

`TIME_EXTRACT(<TIMESTAMP>, [<unit>, [<timezone>]])`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Extracts the value of some unit of the timestamp and returns the number.

## TIME_FLOOR

`TIME_FLOOR(<TIMESTAMP>, <period>, [<origin>, [<timezone>]])`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Rounds down a timestamp by a given time period, optionally from some reference time or timezone.

## TIME_FORMAT

`TIME_FORMAT(<TIMESTAMP>, [<pattern>, [<timezone>]])`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Formats a timestamp as a string.

## TIME_IN_INTERVAL

`TIME_IN_INTERVAL(<TIMESTAMP>, <CHARACTER>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Returns whether a timestamp is contained within a particular interval, formatted as a string.

## TIME_PARSE

`TIME_PARSE(<string_expr>, [<pattern>, [<timezone>]])`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Parses a string into a timestamp.

## TIME_SHIFT

`TIME_SHIFT(<TIMESTAMP>, <period>, <step>, [<timezone>])`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Shifts a timestamp forwards or backwards by a given number of time units.

## TIMESTAMP_TO_MILLIS

`TIMESTAMP_TO_MILLIS(<TIMESTAMP>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Returns the number of milliseconds since epoch for the given timestamp.

## TIMESTAMPADD

`TIMESTAMPADD(<unit>, <count>, <TIMESTAMP>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Adds a certain amount of time to a given timestamp.

## TIMESTAMPDIFF

`TIMESTAMPDIFF(<unit>, <TIMESTAMP>, <TIMESTAMP>)`

**Function type:** [Scalar, date and time](sql-scalar.md#date-and-time-functions)

Takes the difference between two timestamps, returning the results in the given units.

## TRIM

`TRIM([BOTH|LEADING|TRAILING] [<chars> FROM] expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Trims the leading or trailing characters of an expression.

## TRUNC

`TRUNC(expr[, digits])`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Alias for [`TRUNCATE`](#truncate).

## TRUNCATE

`TRUNCATE(expr[, digits])`

**Function type:** [Scalar, numeric](sql-scalar.md#numeric-functions)

Truncates a numerical expression to a specific number of decimal digits.

## UPPER

`UPPER(expr)`

**Function type:** [Scalar, string](sql-scalar.md#string-functions)

Returns the expression in uppercase.

## VAR_POP

`VAR_POP(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Calculates the population variance of a set of values.

## VAR_SAMP

`VAR_SAMP(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Calculates the sample variance of a set of values.

## VARIANCE

`VARIANCE(expr)`

**Function type:** [Aggregation](sql-aggregations.md)

Alias for [`VAR_SAMP`](#var_samp).