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Do not edit it manually as changes will be overwritten.
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# Scalar Functions (NEW)

Note: this documentation is in the process of being migrated to be [automatically created from the codebase].
Please see the [Scalar Functions (old)](aggregate_functions.md) page for
the rest of the documentation.

[automatically created from the codebase]: https://github.com/apache/datafusion/issues/12740

## Math Functions

- [abs](#abs)
- [acos](#acos)
- [acosh](#acosh)
- [asin](#asin)
- [asinh](#asinh)
- [atan](#atan)
- [atan2](#atan2)
- [atanh](#atanh)
- [cbrt](#cbrt)
- [ceil](#ceil)
- [cos](#cos)
- [cosh](#cosh)
- [degrees](#degrees)
- [exp](#exp)
- [factorial](#factorial)
- [floor](#floor)
- [gcd](#gcd)
- [isnan](#isnan)
- [iszero](#iszero)
- [lcm](#lcm)
- [ln](#ln)
- [log](#log)
- [log10](#log10)
- [log2](#log2)
- [nanvl](#nanvl)
- [pi](#pi)
- [pow](#pow)
- [power](#power)
- [radians](#radians)
- [random](#random)
- [round](#round)
- [signum](#signum)
- [sin](#sin)
- [sinh](#sinh)
- [sqrt](#sqrt)
- [tan](#tan)
- [tanh](#tanh)
- [trunc](#trunc)

### `abs`

Returns the absolute value of a number.

```
abs(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `acos`

Returns the arc cosine or inverse cosine of a number.

```
acos(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `acosh`

Returns the area hyperbolic cosine or inverse hyperbolic cosine of a number.

```
acosh(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `asin`

Returns the arc sine or inverse sine of a number.

```
asin(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `asinh`

Returns the area hyperbolic sine or inverse hyperbolic sine of a number.

```
asinh(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `atan`

Returns the arc tangent or inverse tangent of a number.

```
atan(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `atan2`

Returns the arc tangent or inverse tangent of `expression_y / expression_x`.

```
atan2(expression_y, expression_x)
```

#### Arguments

- **expression_y**: First numeric expression to operate on.
  Can be a constant, column, or function, and any combination of arithmetic operators.
- **expression_x**: Second numeric expression to operate on.
  Can be a constant, column, or function, and any combination of arithmetic operators.

### `atanh`

Returns the area hyperbolic tangent or inverse hyperbolic tangent of a number.

```
atanh(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `cbrt`

Returns the cube root of a number.

```
cbrt(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `ceil`

Returns the nearest integer greater than or equal to a number.

```
ceil(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `cos`

Returns the cosine of a number.

```
cos(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `cosh`

Returns the hyperbolic cosine of a number.

```
cosh(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `degrees`

Converts radians to degrees.

```
degrees(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `exp`

Returns the base-e exponential of a number.

```
exp(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `factorial`

Factorial. Returns 1 if value is less than 2.

```
factorial(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `floor`

Returns the nearest integer less than or equal to a number.

```
floor(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `gcd`

Returns the greatest common divisor of `expression_x` and `expression_y`. Returns 0 if both inputs are zero.

```
gcd(expression_x, expression_y)
```

#### Arguments

- **expression_x**: First numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **expression_y**: Second numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `isnan`

Returns true if a given number is +NaN or -NaN otherwise returns false.

```
isnan(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `iszero`

Returns true if a given number is +0.0 or -0.0 otherwise returns false.

```
iszero(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `lcm`

Returns the least common multiple of `expression_x` and `expression_y`. Returns 0 if either input is zero.

```
lcm(expression_x, expression_y)
```

#### Arguments

- **expression_x**: First numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **expression_y**: Second numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `ln`

Returns the natural logarithm of a number.

```
ln(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `log`

Returns the base-x logarithm of a number. Can either provide a specified base, or if omitted then takes the base-10 of a number.

```
log(base, numeric_expression)
log(numeric_expression)
```

#### Arguments

- **base**: Base numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `log10`

Returns the base-10 logarithm of a number.

```
log10(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `log2`

Returns the base-2 logarithm of a number.

```
log2(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `nanvl`

Returns the first argument if it's not _NaN_.
Returns the second argument otherwise.

```
nanvl(expression_x, expression_y)
```

#### Arguments

- **expression_x**: Numeric expression to return if it's not _NaN_. Can be a constant, column, or function, and any combination of arithmetic operators.
- **expression_y**: Numeric expression to return if the first expression is _NaN_. Can be a constant, column, or function, and any combination of arithmetic operators.

### `pi`

Returns an approximate value of π.

```
pi()
```

### `pow`

_Alias of [power](#power)._

### `power`

Returns a base expression raised to the power of an exponent.

```
power(base, exponent)
```

#### Arguments

- **base**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **exponent**: Exponent numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Aliases

- pow

### `radians`

Converts degrees to radians.

```
radians(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `random`

Returns a random float value in the range [0, 1).
The random seed is unique to each row.

```
random()
```

### `round`

Rounds a number to the nearest integer.

```
round(numeric_expression[, decimal_places])
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **decimal_places**: Optional. The number of decimal places to round to. Defaults to 0.

### `signum`

Returns the sign of a number.
Negative numbers return `-1`.
Zero and positive numbers return `1`.

```
signum(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `sin`

Returns the sine of a number.

```
sin(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `sinh`

Returns the hyperbolic sine of a number.

```
sinh(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `sqrt`

Returns the square root of a number.

```
sqrt(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `tan`

Returns the tangent of a number.

```
tan(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `tanh`

Returns the hyperbolic tangent of a number.

```
tanh(numeric_expression)
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.

### `trunc`

Truncates a number to a whole number or truncated to the specified decimal places.

```
trunc(numeric_expression[, decimal_places])
```

#### Arguments

- **numeric_expression**: Numeric expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **decimal_places**: Optional. The number of decimal places to
  truncate to. Defaults to 0 (truncate to a whole number). If
  `decimal_places` is a positive integer, truncates digits to the
  right of the decimal point. If `decimal_places` is a negative
  integer, replaces digits to the left of the decimal point with `0`.

## Conditional Functions

- [coalesce](#coalesce)
- [ifnull](#ifnull)
- [nullif](#nullif)
- [nvl](#nvl)
- [nvl2](#nvl2)

### `coalesce`

Returns the first of its arguments that is not _null_. Returns _null_ if all arguments are _null_. This function is often used to substitute a default value for _null_ values.

```
coalesce(expression1[, ..., expression_n])
```

#### Arguments

- **expression1, expression_n**: Expression to use if previous expressions are _null_. Can be a constant, column, or function, and any combination of arithmetic operators. Pass as many expression arguments as necessary.

#### Example

```sql
> select coalesce(null, null, 'datafusion');
+----------------------------------------+
| coalesce(NULL,NULL,Utf8("datafusion")) |
+----------------------------------------+
| datafusion                             |
+----------------------------------------+
```

### `ifnull`

_Alias of [nvl](#nvl)._

### `nullif`

Returns _null_ if _expression1_ equals _expression2_; otherwise it returns _expression1_.
This can be used to perform the inverse operation of [`coalesce`](#coalesce).

```
nullif(expression1, expression2)
```

#### Arguments

- **expression1**: Expression to compare and return if equal to expression2. Can be a constant, column, or function, and any combination of operators.
- **expression2**: Expression to compare to expression1. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select nullif('datafusion', 'data');
+-----------------------------------------+
| nullif(Utf8("datafusion"),Utf8("data")) |
+-----------------------------------------+
| datafusion                              |
+-----------------------------------------+
> select nullif('datafusion', 'datafusion');
+-----------------------------------------------+
| nullif(Utf8("datafusion"),Utf8("datafusion")) |
+-----------------------------------------------+
|                                               |
+-----------------------------------------------+
```

### `nvl`

Returns _expression2_ if _expression1_ is NULL otherwise it returns _expression1_.

```
nvl(expression1, expression2)
```

#### Arguments

- **expression1**: Expression to return if not null. Can be a constant, column, or function, and any combination of operators.
- **expression2**: Expression to return if expr1 is null. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select nvl(null, 'a');
+---------------------+
| nvl(NULL,Utf8("a")) |
+---------------------+
| a                   |
+---------------------+\
> select nvl('b', 'a');
+--------------------------+
| nvl(Utf8("b"),Utf8("a")) |
+--------------------------+
| b                        |
+--------------------------+
```

#### Aliases

- ifnull

### `nvl2`

Returns _expression2_ if _expression1_ is not NULL; otherwise it returns _expression3_.

```
nvl2(expression1, expression2, expression3)
```

#### Arguments

- **expression1**: Expression to test for null. Can be a constant, column, or function, and any combination of operators.
- **expression2**: Expression to return if expr1 is not null. Can be a constant, column, or function, and any combination of operators.
- **expression3**: Expression to return if expr1 is null. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select nvl2(null, 'a', 'b');
+--------------------------------+
| nvl2(NULL,Utf8("a"),Utf8("b")) |
+--------------------------------+
| b                              |
+--------------------------------+
> select nvl2('data', 'a', 'b');
+----------------------------------------+
| nvl2(Utf8("data"),Utf8("a"),Utf8("b")) |
+----------------------------------------+
| a                                      |
+----------------------------------------+
```

## String Functions

- [ascii](#ascii)
- [bit_length](#bit_length)
- [btrim](#btrim)
- [char_length](#char_length)
- [character_length](#character_length)
- [chr](#chr)
- [concat](#concat)
- [concat_ws](#concat_ws)
- [contains](#contains)
- [ends_with](#ends_with)
- [find_in_set](#find_in_set)
- [initcap](#initcap)
- [instr](#instr)
- [left](#left)
- [length](#length)
- [levenshtein](#levenshtein)
- [lower](#lower)
- [lpad](#lpad)
- [ltrim](#ltrim)
- [octet_length](#octet_length)
- [position](#position)
- [repeat](#repeat)
- [replace](#replace)
- [reverse](#reverse)
- [right](#right)
- [rpad](#rpad)
- [rtrim](#rtrim)
- [split_part](#split_part)
- [starts_with](#starts_with)
- [strpos](#strpos)
- [substr](#substr)
- [substr_index](#substr_index)
- [substring](#substring)
- [substring_index](#substring_index)
- [to_hex](#to_hex)
- [translate](#translate)
- [trim](#trim)
- [upper](#upper)
- [uuid](#uuid)

### `ascii`

Returns the Unicode character code of the first character in a string.

```
ascii(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select ascii('abc');
+--------------------+
| ascii(Utf8("abc")) |
+--------------------+
| 97                 |
+--------------------+
> select ascii('🚀');
+-------------------+
| ascii(Utf8("🚀")) |
+-------------------+
| 128640            |
+-------------------+
```

**Related functions**:

- [chr](#chr)

### `bit_length`

Returns the bit length of a string.

```
bit_length(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select bit_length('datafusion');
+--------------------------------+
| bit_length(Utf8("datafusion")) |
+--------------------------------+
| 80                             |
+--------------------------------+
```

**Related functions**:

- [length](#length)
- [octet_length](#octet_length)

### `btrim`

Trims the specified trim string from the start and end of a string. If no trim string is provided, all whitespace is removed from the start and end of the input string.

```
btrim(str[, trim_str])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **trim_str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators. _Default is whitespace characters._

#### Example

```sql
> select btrim('__datafusion____', '_');
+-------------------------------------------+
| btrim(Utf8("__datafusion____"),Utf8("_")) |
+-------------------------------------------+
| datafusion                                |
+-------------------------------------------+
```

#### Aliases

- trim

**Related functions**:

- [ltrim](#ltrim)
- [rtrim](#rtrim)

### `char_length`

_Alias of [character_length](#character_length)._

### `character_length`

Returns the number of characters in a string.

```
character_length(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select character_length('Ångström');
+------------------------------------+
| character_length(Utf8("Ångström")) |
+------------------------------------+
| 8                                  |
+------------------------------------+
```

#### Aliases

- length
- char_length

**Related functions**:

- [bit_length](#bit_length)
- [octet_length](#octet_length)

### `chr`

Returns the character with the specified ASCII or Unicode code value.

```
chr(expression)
```

#### Arguments

- **expression**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select chr(128640);
+--------------------+
| chr(Int64(128640)) |
+--------------------+
| 🚀                 |
+--------------------+
```

**Related functions**:

- [ascii](#ascii)

### `concat`

Concatenates multiple strings together.

```
concat(str[, ..., str_n])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **str_n**: Subsequent string expressions to concatenate.

#### Example

```sql
> select concat('data', 'f', 'us', 'ion');
+-------------------------------------------------------+
| concat(Utf8("data"),Utf8("f"),Utf8("us"),Utf8("ion")) |
+-------------------------------------------------------+
| datafusion                                            |
+-------------------------------------------------------+
```

**Related functions**:

- [concat_ws](#concat_ws)

### `concat_ws`

Concatenates multiple strings together with a specified separator.

```
concat_ws(separator, str[, ..., str_n])
```

#### Arguments

- **separator**: Separator to insert between concatenated strings.
- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **str_n**: Subsequent string expressions to concatenate. expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select concat_ws('_', 'data', 'fusion');
+--------------------------------------------------+
| concat_ws(Utf8("_"),Utf8("data"),Utf8("fusion")) |
+--------------------------------------------------+
| data_fusion                                      |
+--------------------------------------------------+
```

**Related functions**:

- [concat](#concat)

### `contains`

Return true if search_str is found within string (case-sensitive).

```
contains(str, search_str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **search_str**: The string to search for in str.

#### Example

```sql
> select contains('the quick brown fox', 'row');
+---------------------------------------------------+
| contains(Utf8("the quick brown fox"),Utf8("row")) |
+---------------------------------------------------+
| true                                              |
+---------------------------------------------------+
```

### `ends_with`

Tests if a string ends with a substring.

```
ends_with(str, substr)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **substr**: Substring to test for.

#### Example

```sql
>  select ends_with('datafusion', 'soin');
+--------------------------------------------+
| ends_with(Utf8("datafusion"),Utf8("soin")) |
+--------------------------------------------+
| false                                      |
+--------------------------------------------+
> select ends_with('datafusion', 'sion');
+--------------------------------------------+
| ends_with(Utf8("datafusion"),Utf8("sion")) |
+--------------------------------------------+
| true                                       |
+--------------------------------------------+
```

### `find_in_set`

Returns a value in the range of 1 to N if the string str is in the string list strlist consisting of N substrings.

```
find_in_set(str, strlist)
```

#### Arguments

- **str**: String expression to find in strlist.
- **strlist**: A string list is a string composed of substrings separated by , characters.

#### Example

```sql
> select find_in_set('b', 'a,b,c,d');
+----------------------------------------+
| find_in_set(Utf8("b"),Utf8("a,b,c,d")) |
+----------------------------------------+
| 2                                      |
+----------------------------------------+
```

### `initcap`

Capitalizes the first character in each word in the input string. Words are delimited by non-alphanumeric characters.

```
initcap(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select initcap('apache datafusion');
+------------------------------------+
| initcap(Utf8("apache datafusion")) |
+------------------------------------+
| Apache Datafusion                  |
+------------------------------------+
```

**Related functions**:

- [lower](#lower)
- [upper](#upper)

### `instr`

_Alias of [strpos](#strpos)._

### `left`

Returns a specified number of characters from the left side of a string.

```
left(str, n)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **n**: Number of characters to return.

#### Example

```sql
> select left('datafusion', 4);
+-----------------------------------+
| left(Utf8("datafusion"),Int64(4)) |
+-----------------------------------+
| data                              |
+-----------------------------------+
```

**Related functions**:

- [right](#right)

### `length`

_Alias of [character_length](#character_length)._

### `levenshtein`

Returns the [`Levenshtein distance`](https://en.wikipedia.org/wiki/Levenshtein_distance) between the two given strings.

```
levenshtein(str1, str2)
```

#### Arguments

- **str1**: String expression to compute Levenshtein distance with str2.
- **str2**: String expression to compute Levenshtein distance with str1.

#### Example

```sql
> select levenshtein('kitten', 'sitting');
+---------------------------------------------+
| levenshtein(Utf8("kitten"),Utf8("sitting")) |
+---------------------------------------------+
| 3                                           |
+---------------------------------------------+
```

### `lower`

Converts a string to lower-case.

```
lower(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select lower('Ångström');
+-------------------------+
| lower(Utf8("Ångström")) |
+-------------------------+
| ångström                |
+-------------------------+
```

**Related functions**:

- [initcap](#initcap)
- [upper](#upper)

### `lpad`

Pads the left side of a string with another string to a specified string length.

```
lpad(str, n[, padding_str])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **n**: String length to pad to.
- **padding_str**: Optional string expression to pad with. Can be a constant, column, or function, and any combination of string operators. _Default is a space._

#### Example

```sql
> select lpad('Dolly', 10, 'hello');
+---------------------------------------------+
| lpad(Utf8("Dolly"),Int64(10),Utf8("hello")) |
+---------------------------------------------+
| helloDolly                                  |
+---------------------------------------------+
```

**Related functions**:

- [rpad](#rpad)

### `ltrim`

Trims the specified trim string from the beginning of a string. If no trim string is provided, all whitespace is removed from the start of the input string.

```
ltrim(str[, trim_str])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **trim_str**: String expression to trim from the beginning of the input string. Can be a constant, column, or function, and any combination of arithmetic operators. _Default is whitespace characters._

#### Example

```sql
> select ltrim('  datafusion  ');
+-------------------------------+
| ltrim(Utf8("  datafusion  ")) |
+-------------------------------+
| datafusion                    |
+-------------------------------+
> select ltrim('___datafusion___', '_');
+-------------------------------------------+
| ltrim(Utf8("___datafusion___"),Utf8("_")) |
+-------------------------------------------+
| datafusion___                             |
+-------------------------------------------+
```

**Related functions**:

- [btrim](#btrim)
- [rtrim](#rtrim)

### `octet_length`

Returns the length of a string in bytes.

```
octet_length(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select octet_length('Ångström');
+--------------------------------+
| octet_length(Utf8("Ångström")) |
+--------------------------------+
| 10                             |
+--------------------------------+
```

**Related functions**:

- [bit_length](#bit_length)
- [length](#length)

### `position`

_Alias of [strpos](#strpos)._

### `repeat`

Returns a string with an input string repeated a specified number.

```
repeat(str, n)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **n**: Number of times to repeat the input string.

#### Example

```sql
> select repeat('data', 3);
+-------------------------------+
| repeat(Utf8("data"),Int64(3)) |
+-------------------------------+
| datadatadata                  |
+-------------------------------+
```

### `replace`

Replaces all occurrences of a specified substring in a string with a new substring.

```
replace(str, substr, replacement)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **substr**: Substring expression to replace in the input string. Substring expression expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **replacement**: Replacement substring expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select replace('ABabbaBA', 'ab', 'cd');
+-------------------------------------------------+
| replace(Utf8("ABabbaBA"),Utf8("ab"),Utf8("cd")) |
+-------------------------------------------------+
| ABcdbaBA                                        |
+-------------------------------------------------+
```

### `reverse`

Reverses the character order of a string.

```
reverse(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select reverse('datafusion');
+-----------------------------+
| reverse(Utf8("datafusion")) |
+-----------------------------+
| noisufatad                  |
+-----------------------------+
```

### `right`

Returns a specified number of characters from the right side of a string.

```
right(str, n)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **n**: Number of characters to return

#### Example

```sql
> select right('datafusion', 6);
+------------------------------------+
| right(Utf8("datafusion"),Int64(6)) |
+------------------------------------+
| fusion                             |
+------------------------------------+
```

**Related functions**:

- [left](#left)

### `rpad`

Pads the right side of a string with another string to a specified string length.

```
rpad(str, n[, padding_str])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **n**: String length to pad to.
- **padding_str**: String expression to pad with. Can be a constant, column, or function, and any combination of string operators. _Default is a space._

#### Example

```sql
>  select rpad('datafusion', 20, '_-');
+-----------------------------------------------+
| rpad(Utf8("datafusion"),Int64(20),Utf8("_-")) |
+-----------------------------------------------+
| datafusion_-_-_-_-_-                          |
+-----------------------------------------------+
```

**Related functions**:

- [lpad](#lpad)

### `rtrim`

Trims the specified trim string from the end of a string. If no trim string is provided, all whitespace is removed from the end of the input string.

```
rtrim(str[, trim_str])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **trim_str**: String expression to trim from the end of the input string. Can be a constant, column, or function, and any combination of arithmetic operators. _Default is whitespace characters._

#### Example

```sql
> select rtrim('  datafusion  ');
+-------------------------------+
| rtrim(Utf8("  datafusion  ")) |
+-------------------------------+
|   datafusion                  |
+-------------------------------+
> select rtrim('___datafusion___', '_');
+-------------------------------------------+
| rtrim(Utf8("___datafusion___"),Utf8("_")) |
+-------------------------------------------+
| ___datafusion                             |
+-------------------------------------------+
```

**Related functions**:

- [btrim](#btrim)
- [ltrim](#ltrim)

### `split_part`

Splits a string based on a specified delimiter and returns the substring in the specified position.

```
split_part(str, delimiter, pos)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **delimiter**: String or character to split on.
- **pos**: Position of the part to return.

#### Example

```sql
> select split_part('1.2.3.4.5', '.', 3);
+--------------------------------------------------+
| split_part(Utf8("1.2.3.4.5"),Utf8("."),Int64(3)) |
+--------------------------------------------------+
| 3                                                |
+--------------------------------------------------+
```

### `starts_with`

Tests if a string starts with a substring.

```
starts_with(str, substr)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **substr**: Substring to test for.

#### Example

```sql
> select starts_with('datafusion','data');
+----------------------------------------------+
| starts_with(Utf8("datafusion"),Utf8("data")) |
+----------------------------------------------+
| true                                         |
+----------------------------------------------+
```

### `strpos`

Returns the starting position of a specified substring in a string. Positions begin at 1. If the substring does not exist in the string, the function returns 0.

```
strpos(str, substr)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **substr**: Substring expression to search for.

#### Example

```sql
> select strpos('datafusion', 'fus');
+----------------------------------------+
| strpos(Utf8("datafusion"),Utf8("fus")) |
+----------------------------------------+
| 5                                      |
+----------------------------------------+
```

#### Aliases

- instr
- position

### `substr`

Extracts a substring of a specified number of characters from a specific starting position in a string.

```
substr(str, start_pos[, length])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **start_pos**: Character position to start the substring at. The first character in the string has a position of 1.
- **length**: Number of characters to extract. If not specified, returns the rest of the string after the start position.

#### Example

```sql
> select substr('datafusion', 5, 3);
+----------------------------------------------+
| substr(Utf8("datafusion"),Int64(5),Int64(3)) |
+----------------------------------------------+
| fus                                          |
+----------------------------------------------+
```

#### Aliases

- substring

### `substr_index`

Returns the substring from str before count occurrences of the delimiter delim.
If count is positive, everything to the left of the final delimiter (counting from the left) is returned.
If count is negative, everything to the right of the final delimiter (counting from the right) is returned.

```
substr_index(str, delim, count)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **delim**: The string to find in str to split str.
- **count**: The number of times to search for the delimiter. Can be either a positive or negative number.

#### Example

```sql
> select substr_index('www.apache.org', '.', 1);
+---------------------------------------------------------+
| substr_index(Utf8("www.apache.org"),Utf8("."),Int64(1)) |
+---------------------------------------------------------+
| www                                                     |
+---------------------------------------------------------+
> select substr_index('www.apache.org', '.', -1);
+----------------------------------------------------------+
| substr_index(Utf8("www.apache.org"),Utf8("."),Int64(-1)) |
+----------------------------------------------------------+
| org                                                      |
+----------------------------------------------------------+
```

#### Aliases

- substring_index

### `substring`

_Alias of [substr](#substr)._

### `substring_index`

_Alias of [substr_index](#substr_index)._

### `to_hex`

Converts an integer to a hexadecimal string.

```
to_hex(int)
```

#### Arguments

- **int**: Integer expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select to_hex(12345689);
+-------------------------+
| to_hex(Int64(12345689)) |
+-------------------------+
| bc6159                  |
+-------------------------+
```

### `translate`

Translates characters in a string to specified translation characters.

```
translate(str, chars, translation)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **chars**: Characters to translate.
- **translation**: Translation characters. Translation characters replace only characters at the same position in the **chars** string.

#### Example

```sql
> select translate('twice', 'wic', 'her');
+--------------------------------------------------+
| translate(Utf8("twice"),Utf8("wic"),Utf8("her")) |
+--------------------------------------------------+
| there                                            |
+--------------------------------------------------+
```

### `trim`

_Alias of [btrim](#btrim)._

### `upper`

Converts a string to upper-case.

```
upper(str)
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select upper('dataFusion');
+---------------------------+
| upper(Utf8("dataFusion")) |
+---------------------------+
| DATAFUSION                |
+---------------------------+
```

**Related functions**:

- [initcap](#initcap)
- [lower](#lower)

### `uuid`

Returns [`UUID v4`](<https://en.wikipedia.org/wiki/Universally_unique_identifier#Version_4_(random)>) string value which is unique per row.

```
uuid()
```

#### Example

```sql
> select uuid();
+--------------------------------------+
| uuid()                               |
+--------------------------------------+
| 6ec17ef8-1934-41cc-8d59-d0c8f9eea1f0 |
+--------------------------------------+
```

## Binary String Functions

- [decode](#decode)
- [encode](#encode)

### `decode`

Decode binary data from textual representation in string.

```
decode(expression, format)
```

#### Arguments

- **expression**: Expression containing encoded string data
- **format**: Same arguments as [encode](#encode)

**Related functions**:

- [encode](#encode)

### `encode`

Encode binary data into a textual representation.

```
encode(expression, format)
```

#### Arguments

- **expression**: Expression containing string or binary data
- **format**: Supported formats are: `base64`, `hex`

**Related functions**:

- [decode](#decode)

## Regular Expression Functions

Apache DataFusion uses a [PCRE-like](https://en.wikibooks.org/wiki/Regular_Expressions/Perl-Compatible_Regular_Expressions)
regular expression [syntax](https://docs.rs/regex/latest/regex/#syntax)
(minus support for several features including look-around and backreferences).
The following regular expression functions are supported:

- [regexp_like](#regexp_like)
- [regexp_match](#regexp_match)
- [regexp_replace](#regexp_replace)

### `regexp_like`

Returns true if a [regular expression](https://docs.rs/regex/latest/regex/#syntax) has at least one match in a string, false otherwise.

```
regexp_like(str, regexp[, flags])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **regexp**: Regular expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **flags**: Optional regular expression flags that control the behavior of the regular expression. The following flags are supported:
  - **i**: case-insensitive: letters match both upper and lower case
  - **m**: multi-line mode: ^ and $ match begin/end of line
  - **s**: allow . to match \n
  - **R**: enables CRLF mode: when multi-line mode is enabled, \r\n is used
  - **U**: swap the meaning of x* and x*?

#### Example

```sql
select regexp_like('Köln', '[a-zA-Z]ö[a-zA-Z]{2}');
+--------------------------------------------------------+
| regexp_like(Utf8("Köln"),Utf8("[a-zA-Z]ö[a-zA-Z]{2}")) |
+--------------------------------------------------------+
| true                                                   |
+--------------------------------------------------------+
SELECT regexp_like('aBc', '(b|d)', 'i');
+--------------------------------------------------+
| regexp_like(Utf8("aBc"),Utf8("(b|d)"),Utf8("i")) |
+--------------------------------------------------+
| true                                             |
+--------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/regexp.rs)

### `regexp_match`

Returns a list of [regular expression](https://docs.rs/regex/latest/regex/#syntax) matches in a string.

```
regexp_match(str, regexp[, flags])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **regexp**: Regular expression to match against.
  Can be a constant, column, or function.
- **flags**: Optional regular expression flags that control the behavior of the regular expression. The following flags are supported:
  - **i**: case-insensitive: letters match both upper and lower case
  - **m**: multi-line mode: ^ and $ match begin/end of line
  - **s**: allow . to match \n
  - **R**: enables CRLF mode: when multi-line mode is enabled, \r\n is used
  - **U**: swap the meaning of x* and x*?

#### Example

```sql
            > select regexp_match('Köln', '[a-zA-Z]ö[a-zA-Z]{2}');
            +---------------------------------------------------------+
            | regexp_match(Utf8("Köln"),Utf8("[a-zA-Z]ö[a-zA-Z]{2}")) |
            +---------------------------------------------------------+
            | [Köln]                                                  |
            +---------------------------------------------------------+
            SELECT regexp_match('aBc', '(b|d)', 'i');
            +---------------------------------------------------+
            | regexp_match(Utf8("aBc"),Utf8("(b|d)"),Utf8("i")) |
            +---------------------------------------------------+
            | [B]                                               |
            +---------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/regexp.rs)

### `regexp_replace`

Replaces substrings in a string that match a [regular expression](https://docs.rs/regex/latest/regex/#syntax).

```
regexp_replace(str, regexp, replacement[, flags])
```

#### Arguments

- **str**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **regexp**: Regular expression to match against.
  Can be a constant, column, or function.
- **replacement**: Replacement string expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **flags**: Optional regular expression flags that control the behavior of the regular expression. The following flags are supported:
- **g**: (global) Search globally and don't return after the first match
- **i**: case-insensitive: letters match both upper and lower case
- **m**: multi-line mode: ^ and $ match begin/end of line
- **s**: allow . to match \n
- **R**: enables CRLF mode: when multi-line mode is enabled, \r\n is used
- **U**: swap the meaning of x* and x*?

#### Example

```sql
> select regexp_replace('foobarbaz', 'b(..)', 'X\\1Y', 'g');
+------------------------------------------------------------------------+
| regexp_replace(Utf8("foobarbaz"),Utf8("b(..)"),Utf8("X\1Y"),Utf8("g")) |
+------------------------------------------------------------------------+
| fooXarYXazY                                                            |
+------------------------------------------------------------------------+
SELECT regexp_replace('aBc', '(b|d)', 'Ab\\1a', 'i');
+-------------------------------------------------------------------+
| regexp_replace(Utf8("aBc"),Utf8("(b|d)"),Utf8("Ab\1a"),Utf8("i")) |
+-------------------------------------------------------------------+
| aAbBac                                                            |
+-------------------------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/regexp.rs)

## Time and Date Functions

- [current_date](#current_date)
- [current_time](#current_time)
- [current_timestamp](#current_timestamp)
- [date_bin](#date_bin)
- [date_format](#date_format)
- [date_part](#date_part)
- [date_trunc](#date_trunc)
- [datepart](#datepart)
- [datetrunc](#datetrunc)
- [from_unixtime](#from_unixtime)
- [make_date](#make_date)
- [now](#now)
- [to_char](#to_char)
- [to_date](#to_date)
- [to_local_time](#to_local_time)
- [to_timestamp](#to_timestamp)
- [to_timestamp_micros](#to_timestamp_micros)
- [to_timestamp_millis](#to_timestamp_millis)
- [to_timestamp_nanos](#to_timestamp_nanos)
- [to_timestamp_seconds](#to_timestamp_seconds)
- [to_unixtime](#to_unixtime)
- [today](#today)

### `current_date`

Returns the current UTC date.

The `current_date()` return value is determined at query time and will return the same date, no matter when in the query plan the function executes.

```
current_date()
```

#### Aliases

- today

### `current_time`

Returns the current UTC time.

The `current_time()` return value is determined at query time and will return the same time, no matter when in the query plan the function executes.

```
current_time()
```

### `current_timestamp`

_Alias of [now](#now)._

### `date_bin`

Calculates time intervals and returns the start of the interval nearest to the specified timestamp. Use `date_bin` to downsample time series data by grouping rows into time-based "bins" or "windows" and applying an aggregate or selector function to each window.

For example, if you "bin" or "window" data into 15 minute intervals, an input timestamp of `2023-01-01T18:18:18Z` will be updated to the start time of the 15 minute bin it is in: `2023-01-01T18:15:00Z`.

```
date_bin(interval, expression, origin-timestamp)
```

#### Arguments

- **interval**: Bin interval.
- **expression**: Time expression to operate on. Can be a constant, column, or function.
- **origin-timestamp**: Optional. Starting point used to determine bin boundaries. If not specified defaults 1970-01-01T00:00:00Z (the UNIX epoch in UTC).

The following intervals are supported:

- nanoseconds
- microseconds
- milliseconds
- seconds
- minutes
- hours
- days
- weeks
- months
- years
- century

### `date_format`

_Alias of [to_char](#to_char)._

### `date_part`

Returns the specified part of the date as an integer.

```
date_part(part, expression)
```

#### Arguments

- **part**: Part of the date to return. The following date parts are supported:

  - year
  - quarter (emits value in inclusive range [1, 4] based on which quartile of the year the date is in)
  - month
  - week (week of the year)
  - day (day of the month)
  - hour
  - minute
  - second
  - millisecond
  - microsecond
  - nanosecond
  - dow (day of the week)
  - doy (day of the year)
  - epoch (seconds since Unix epoch)

- **expression**: Time expression to operate on. Can be a constant, column, or function.

#### Aliases

- datepart

### `date_trunc`

Truncates a timestamp value to a specified precision.

```
date_trunc(precision, expression)
```

#### Arguments

- **precision**: Time precision to truncate to. The following precisions are supported:

  - year / YEAR
  - quarter / QUARTER
  - month / MONTH
  - week / WEEK
  - day / DAY
  - hour / HOUR
  - minute / MINUTE
  - second / SECOND

- **expression**: Time expression to operate on. Can be a constant, column, or function.

#### Aliases

- datetrunc

### `datepart`

_Alias of [date_part](#date_part)._

### `datetrunc`

_Alias of [date_trunc](#date_trunc)._

### `from_unixtime`

Converts an integer to RFC3339 timestamp format (`YYYY-MM-DDT00:00:00.000000000Z`). Integers and unsigned integers are interpreted as nanoseconds since the unix epoch (`1970-01-01T00:00:00Z`) return the corresponding timestamp.

```
from_unixtime(expression)
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function, and any combination of arithmetic operators.

### `make_date`

Make a date from year/month/day component parts.

```
make_date(year, month, day)
```

#### Arguments

- **year**: Year to use when making the date. Can be a constant, column or function, and any combination of arithmetic operators.
- **month**: Month to use when making the date. Can be a constant, column or function, and any combination of arithmetic operators.
- **day**: Day to use when making the date. Can be a constant, column or function, and any combination of arithmetic operators.

#### Example

```sql
> select make_date(2023, 1, 31);
+-------------------------------------------+
| make_date(Int64(2023),Int64(1),Int64(31)) |
+-------------------------------------------+
| 2023-01-31                                |
+-------------------------------------------+
> select make_date('2023', '01', '31');
+-----------------------------------------------+
| make_date(Utf8("2023"),Utf8("01"),Utf8("31")) |
+-----------------------------------------------+
| 2023-01-31                                    |
+-----------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/make_date.rs)

### `now`

Returns the current UTC timestamp.

The `now()` return value is determined at query time and will return the same timestamp, no matter when in the query plan the function executes.

```
now()
```

#### Aliases

- current_timestamp

### `to_char`

Returns a string representation of a date, time, timestamp or duration based on a [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html). Unlike the PostgreSQL equivalent of this function numerical formatting is not supported.

```
to_char(expression, format)
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function that results in a date, time, timestamp or duration.
- **format**: A [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) string to use to convert the expression.
- **day**: Day to use when making the date. Can be a constant, column or function, and any combination of arithmetic operators.

#### Example

```sql
> select to_char('2023-03-01'::date, '%d-%m-%Y');
+----------------------------------------------+
| to_char(Utf8("2023-03-01"),Utf8("%d-%m-%Y")) |
+----------------------------------------------+
| 01-03-2023                                   |
+----------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/to_char.rs)

#### Aliases

- date_format

### `to_date`

Converts a value to a date (`YYYY-MM-DD`).
Supports strings, integer and double types as input.
Strings are parsed as YYYY-MM-DD (e.g. '2023-07-20') if no [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html)s are provided.
Integers and doubles are interpreted as days since the unix epoch (`1970-01-01T00:00:00Z`).
Returns the corresponding date.

Note: `to_date` returns Date32, which represents its values as the number of days since unix epoch(`1970-01-01`) stored as signed 32 bit value. The largest supported date value is `9999-12-31`.

```
to_date('2017-05-31', '%Y-%m-%d')
```

#### Arguments

- **expression**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **format_n**: Optional [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) strings to use to parse the expression. Formats will be tried in the order
  they appear with the first successful one being returned. If none of the formats successfully parse the expression
  an error will be returned.

#### Example

```sql
> select to_date('2023-01-31');
+-----------------------------+
| to_date(Utf8("2023-01-31")) |
+-----------------------------+
| 2023-01-31                  |
+-----------------------------+
> select to_date('2023/01/31', '%Y-%m-%d', '%Y/%m/%d');
+---------------------------------------------------------------+
| to_date(Utf8("2023/01/31"),Utf8("%Y-%m-%d"),Utf8("%Y/%m/%d")) |
+---------------------------------------------------------------+
| 2023-01-31                                                    |
+---------------------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/to_date.rs)

### `to_local_time`

Converts a timestamp with a timezone to a timestamp without a timezone (with no offset or timezone information). This function handles daylight saving time changes.

```
to_local_time(expression)
```

#### Arguments

- **expression**: Time expression to operate on. Can be a constant, column, or function.

#### Example

```sql
> SELECT to_local_time('2024-04-01T00:00:20Z'::timestamp);
+---------------------------------------------+
| to_local_time(Utf8("2024-04-01T00:00:20Z")) |
+---------------------------------------------+
| 2024-04-01T00:00:20                         |
+---------------------------------------------+

> SELECT to_local_time('2024-04-01T00:00:20Z'::timestamp AT TIME ZONE 'Europe/Brussels');
+---------------------------------------------+
| to_local_time(Utf8("2024-04-01T00:00:20Z")) |
+---------------------------------------------+
| 2024-04-01T00:00:20                         |
+---------------------------------------------+

> SELECT
  time,
  arrow_typeof(time) as type,
  to_local_time(time) as to_local_time,
  arrow_typeof(to_local_time(time)) as to_local_time_type
FROM (
  SELECT '2024-04-01T00:00:20Z'::timestamp AT TIME ZONE 'Europe/Brussels' AS time
);
+---------------------------+------------------------------------------------+---------------------+-----------------------------+
| time                      | type                                           | to_local_time       | to_local_time_type          |
+---------------------------+------------------------------------------------+---------------------+-----------------------------+
| 2024-04-01T00:00:20+02:00 | Timestamp(Nanosecond, Some("Europe/Brussels")) | 2024-04-01T00:00:20 | Timestamp(Nanosecond, None) |
+---------------------------+------------------------------------------------+---------------------+-----------------------------+

# combine `to_local_time()` with `date_bin()` to bin on boundaries in the timezone rather
# than UTC boundaries

> SELECT date_bin(interval '1 day', to_local_time('2024-04-01T00:00:20Z'::timestamp AT TIME ZONE 'Europe/Brussels')) AS date_bin;
+---------------------+
| date_bin            |
+---------------------+
| 2024-04-01T00:00:00 |
+---------------------+

> SELECT date_bin(interval '1 day', to_local_time('2024-04-01T00:00:20Z'::timestamp AT TIME ZONE 'Europe/Brussels')) AT TIME ZONE 'Europe/Brussels' AS date_bin_with_timezone;
+---------------------------+
| date_bin_with_timezone    |
+---------------------------+
| 2024-04-01T00:00:00+02:00 |
+---------------------------+
```

### `to_timestamp`

Converts a value to a timestamp (`YYYY-MM-DDT00:00:00Z`). Supports strings, integer, unsigned integer, and double types as input. Strings are parsed as RFC3339 (e.g. '2023-07-20T05:44:00') if no [Chrono formats] are provided. Integers, unsigned integers, and doubles are interpreted as seconds since the unix epoch (`1970-01-01T00:00:00Z`). Returns the corresponding timestamp.

Note: `to_timestamp` returns `Timestamp(Nanosecond)`. The supported range for integer input is between `-9223372037` and `9223372036`. Supported range for string input is between `1677-09-21T00:12:44.0` and `2262-04-11T23:47:16.0`. Please use `to_timestamp_seconds` for the input outside of supported bounds.

```
to_timestamp(expression[, ..., format_n])
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function, and any combination of arithmetic operators.
- **format_n**: Optional [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) strings to use to parse the expression. Formats will be tried in the order they appear with the first successful one being returned. If none of the formats successfully parse the expression an error will be returned.

#### Example

```sql
> select to_timestamp('2023-01-31T09:26:56.123456789-05:00');
+-----------------------------------------------------------+
| to_timestamp(Utf8("2023-01-31T09:26:56.123456789-05:00")) |
+-----------------------------------------------------------+
| 2023-01-31T14:26:56.123456789                             |
+-----------------------------------------------------------+
> select to_timestamp('03:59:00.123456789 05-17-2023', '%c', '%+', '%H:%M:%S%.f %m-%d-%Y');
+--------------------------------------------------------------------------------------------------------+
| to_timestamp(Utf8("03:59:00.123456789 05-17-2023"),Utf8("%c"),Utf8("%+"),Utf8("%H:%M:%S%.f %m-%d-%Y")) |
+--------------------------------------------------------------------------------------------------------+
| 2023-05-17T03:59:00.123456789                                                                          |
+--------------------------------------------------------------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/to_timestamp.rs)

### `to_timestamp_micros`

Converts a value to a timestamp (`YYYY-MM-DDT00:00:00.000000Z`). Supports strings, integer, and unsigned integer types as input. Strings are parsed as RFC3339 (e.g. '2023-07-20T05:44:00') if no [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html)s are provided. Integers and unsigned integers are interpreted as microseconds since the unix epoch (`1970-01-01T00:00:00Z`) Returns the corresponding timestamp.

```
to_timestamp_micros(expression[, ..., format_n])
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function, and any combination of arithmetic operators.
- **format_n**: Optional [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) strings to use to parse the expression. Formats will be tried in the order they appear with the first successful one being returned. If none of the formats successfully parse the expression an error will be returned.

#### Example

```sql
> select to_timestamp_micros('2023-01-31T09:26:56.123456789-05:00');
+------------------------------------------------------------------+
| to_timestamp_micros(Utf8("2023-01-31T09:26:56.123456789-05:00")) |
+------------------------------------------------------------------+
| 2023-01-31T14:26:56.123456                                       |
+------------------------------------------------------------------+
> select to_timestamp_micros('03:59:00.123456789 05-17-2023', '%c', '%+', '%H:%M:%S%.f %m-%d-%Y');
+---------------------------------------------------------------------------------------------------------------+
| to_timestamp_micros(Utf8("03:59:00.123456789 05-17-2023"),Utf8("%c"),Utf8("%+"),Utf8("%H:%M:%S%.f %m-%d-%Y")) |
+---------------------------------------------------------------------------------------------------------------+
| 2023-05-17T03:59:00.123456                                                                                    |
+---------------------------------------------------------------------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/to_timestamp.rs)

### `to_timestamp_millis`

Converts a value to a timestamp (`YYYY-MM-DDT00:00:00.000Z`). Supports strings, integer, and unsigned integer types as input. Strings are parsed as RFC3339 (e.g. '2023-07-20T05:44:00') if no [Chrono formats](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) are provided. Integers and unsigned integers are interpreted as milliseconds since the unix epoch (`1970-01-01T00:00:00Z`). Returns the corresponding timestamp.

```
to_timestamp_millis(expression[, ..., format_n])
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function, and any combination of arithmetic operators.
- **format_n**: Optional [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) strings to use to parse the expression. Formats will be tried in the order they appear with the first successful one being returned. If none of the formats successfully parse the expression an error will be returned.

#### Example

```sql
> select to_timestamp_millis('2023-01-31T09:26:56.123456789-05:00');
+------------------------------------------------------------------+
| to_timestamp_millis(Utf8("2023-01-31T09:26:56.123456789-05:00")) |
+------------------------------------------------------------------+
| 2023-01-31T14:26:56.123                                          |
+------------------------------------------------------------------+
> select to_timestamp_millis('03:59:00.123456789 05-17-2023', '%c', '%+', '%H:%M:%S%.f %m-%d-%Y');
+---------------------------------------------------------------------------------------------------------------+
| to_timestamp_millis(Utf8("03:59:00.123456789 05-17-2023"),Utf8("%c"),Utf8("%+"),Utf8("%H:%M:%S%.f %m-%d-%Y")) |
+---------------------------------------------------------------------------------------------------------------+
| 2023-05-17T03:59:00.123                                                                                       |
+---------------------------------------------------------------------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/to_timestamp.rs)

### `to_timestamp_nanos`

Converts a value to a timestamp (`YYYY-MM-DDT00:00:00.000000000Z`). Supports strings, integer, and unsigned integer types as input. Strings are parsed as RFC3339 (e.g. '2023-07-20T05:44:00') if no [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html)s are provided. Integers and unsigned integers are interpreted as nanoseconds since the unix epoch (`1970-01-01T00:00:00Z`). Returns the corresponding timestamp.

```
to_timestamp_nanos(expression[, ..., format_n])
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function, and any combination of arithmetic operators.
- **format_n**: Optional [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) strings to use to parse the expression. Formats will be tried in the order they appear with the first successful one being returned. If none of the formats successfully parse the expression an error will be returned.

#### Example

```sql
> select to_timestamp_nanos('2023-01-31T09:26:56.123456789-05:00');
+-----------------------------------------------------------------+
| to_timestamp_nanos(Utf8("2023-01-31T09:26:56.123456789-05:00")) |
+-----------------------------------------------------------------+
| 2023-01-31T14:26:56.123456789                                   |
+-----------------------------------------------------------------+
> select to_timestamp_nanos('03:59:00.123456789 05-17-2023', '%c', '%+', '%H:%M:%S%.f %m-%d-%Y');
+--------------------------------------------------------------------------------------------------------------+
| to_timestamp_nanos(Utf8("03:59:00.123456789 05-17-2023"),Utf8("%c"),Utf8("%+"),Utf8("%H:%M:%S%.f %m-%d-%Y")) |
+--------------------------------------------------------------------------------------------------------------+
| 2023-05-17T03:59:00.123456789                                                                                |
+---------------------------------------------------------------------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/to_timestamp.rs)

### `to_timestamp_seconds`

Converts a value to a timestamp (`YYYY-MM-DDT00:00:00.000Z`). Supports strings, integer, and unsigned integer types as input. Strings are parsed as RFC3339 (e.g. '2023-07-20T05:44:00') if no [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html)s are provided. Integers and unsigned integers are interpreted as seconds since the unix epoch (`1970-01-01T00:00:00Z`). Returns the corresponding timestamp.

```
to_timestamp_seconds(expression[, ..., format_n])
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function, and any combination of arithmetic operators.
- **format_n**: Optional [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) strings to use to parse the expression. Formats will be tried in the order they appear with the first successful one being returned. If none of the formats successfully parse the expression an error will be returned.

#### Example

```sql
> select to_timestamp_seconds('2023-01-31T09:26:56.123456789-05:00');
+-------------------------------------------------------------------+
| to_timestamp_seconds(Utf8("2023-01-31T09:26:56.123456789-05:00")) |
+-------------------------------------------------------------------+
| 2023-01-31T14:26:56                                               |
+-------------------------------------------------------------------+
> select to_timestamp_seconds('03:59:00.123456789 05-17-2023', '%c', '%+', '%H:%M:%S%.f %m-%d-%Y');
+----------------------------------------------------------------------------------------------------------------+
| to_timestamp_seconds(Utf8("03:59:00.123456789 05-17-2023"),Utf8("%c"),Utf8("%+"),Utf8("%H:%M:%S%.f %m-%d-%Y")) |
+----------------------------------------------------------------------------------------------------------------+
| 2023-05-17T03:59:00                                                                                            |
+----------------------------------------------------------------------------------------------------------------+
```

Additional examples can be found [here](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/to_timestamp.rs)

### `to_unixtime`

Converts a value to seconds since the unix epoch (`1970-01-01T00:00:00Z`). Supports strings, dates, timestamps and double types as input. Strings are parsed as RFC3339 (e.g. '2023-07-20T05:44:00') if no [Chrono formats](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) are provided.

```
to_unixtime(expression[, ..., format_n])
```

#### Arguments

- **expression**: Expression to operate on. Can be a constant, column, or function, and any combination of arithmetic operators.
- **format_n**: Optional [Chrono format](https://docs.rs/chrono/latest/chrono/format/strftime/index.html) strings to use to parse the expression. Formats will be tried in the order they appear with the first successful one being returned. If none of the formats successfully parse the expression an error will be returned.

#### Example

```sql
> select to_unixtime('2020-09-08T12:00:00+00:00');
+------------------------------------------------+
| to_unixtime(Utf8("2020-09-08T12:00:00+00:00")) |
+------------------------------------------------+
| 1599566400                                     |
+------------------------------------------------+
> select to_unixtime('01-14-2023 01:01:30+05:30', '%q', '%d-%m-%Y %H/%M/%S', '%+', '%m-%d-%Y %H:%M:%S%#z');
+-----------------------------------------------------------------------------------------------------------------------------+
| to_unixtime(Utf8("01-14-2023 01:01:30+05:30"),Utf8("%q"),Utf8("%d-%m-%Y %H/%M/%S"),Utf8("%+"),Utf8("%m-%d-%Y %H:%M:%S%#z")) |
+-----------------------------------------------------------------------------------------------------------------------------+
| 1673638290                                                                                                                  |
+-----------------------------------------------------------------------------------------------------------------------------+
```

### `today`

_Alias of [current_date](#current_date)._

## Array Functions

- [array_any_value](#array_any_value)
- [array_append](#array_append)
- [array_cat](#array_cat)
- [array_concat](#array_concat)
- [array_contains](#array_contains)
- [array_dims](#array_dims)
- [array_distance](#array_distance)
- [array_distinct](#array_distinct)
- [array_element](#array_element)
- [array_empty](#array_empty)
- [array_except](#array_except)
- [array_extract](#array_extract)
- [array_has](#array_has)
- [array_has_all](#array_has_all)
- [array_has_any](#array_has_any)
- [array_indexof](#array_indexof)
- [array_intersect](#array_intersect)
- [array_join](#array_join)
- [array_length](#array_length)
- [array_ndims](#array_ndims)
- [array_pop_back](#array_pop_back)
- [array_pop_front](#array_pop_front)
- [array_position](#array_position)
- [array_positions](#array_positions)
- [array_prepend](#array_prepend)
- [array_push_back](#array_push_back)
- [array_push_front](#array_push_front)
- [array_remove](#array_remove)
- [array_remove_all](#array_remove_all)
- [array_remove_n](#array_remove_n)
- [array_repeat](#array_repeat)
- [array_replace](#array_replace)
- [array_replace_all](#array_replace_all)
- [array_replace_n](#array_replace_n)
- [array_resize](#array_resize)
- [array_reverse](#array_reverse)
- [array_slice](#array_slice)
- [array_sort](#array_sort)
- [array_to_string](#array_to_string)
- [array_union](#array_union)
- [cardinality](#cardinality)
- [empty](#empty)
- [flatten](#flatten)
- [generate_series](#generate_series)
- [list_any_value](#list_any_value)
- [list_append](#list_append)
- [list_cat](#list_cat)
- [list_concat](#list_concat)
- [list_contains](#list_contains)
- [list_dims](#list_dims)
- [list_distance](#list_distance)
- [list_distinct](#list_distinct)
- [list_element](#list_element)
- [list_empty](#list_empty)
- [list_except](#list_except)
- [list_extract](#list_extract)
- [list_has](#list_has)
- [list_has_all](#list_has_all)
- [list_has_any](#list_has_any)
- [list_indexof](#list_indexof)
- [list_intersect](#list_intersect)
- [list_join](#list_join)
- [list_length](#list_length)
- [list_ndims](#list_ndims)
- [list_pop_back](#list_pop_back)
- [list_pop_front](#list_pop_front)
- [list_position](#list_position)
- [list_positions](#list_positions)
- [list_prepend](#list_prepend)
- [list_push_back](#list_push_back)
- [list_push_front](#list_push_front)
- [list_remove](#list_remove)
- [list_remove_all](#list_remove_all)
- [list_remove_n](#list_remove_n)
- [list_repeat](#list_repeat)
- [list_replace](#list_replace)
- [list_replace_all](#list_replace_all)
- [list_replace_n](#list_replace_n)
- [list_resize](#list_resize)
- [list_reverse](#list_reverse)
- [list_slice](#list_slice)
- [list_sort](#list_sort)
- [list_to_string](#list_to_string)
- [list_union](#list_union)
- [make_array](#make_array)
- [make_list](#make_list)
- [range](#range)
- [string_to_array](#string_to_array)
- [string_to_list](#string_to_list)

### `array_any_value`

Extracts the element with the index n from the array.

```
array_element(array, index)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **index**: Index to extract the element from the array.

#### Example

```sql
> select array_element([1, 2, 3, 4], 3);
+-----------------------------------------+
| array_element(List([1,2,3,4]),Int64(3)) |
+-----------------------------------------+
| 3                                       |
+-----------------------------------------+
```

#### Aliases

- list_any_value

### `array_append`

Appends an element to the end of an array.

```
array_append(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to append to the array.

#### Example

```sql
> select array_append([1, 2, 3], 4);
+--------------------------------------+
| array_append(List([1,2,3]),Int64(4)) |
+--------------------------------------+
| [1, 2, 3, 4]                         |
+--------------------------------------+
```

#### Aliases

- list_append
- array_push_back
- list_push_back

### `array_cat`

_Alias of [array_concat](#array_concat)._

### `array_concat`

Appends an element to the end of an array.

```
array_append(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to append to the array.

#### Example

```sql
> select array_append([1, 2, 3], 4);
+--------------------------------------+
| array_append(List([1,2,3]),Int64(4)) |
+--------------------------------------+
| [1, 2, 3, 4]                         |
+--------------------------------------+
```

#### Aliases

- array_cat
- list_concat
- list_cat

### `array_contains`

_Alias of [array_has](#array_has)._

### `array_dims`

Returns an array of the array's dimensions.

```
array_dims(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_dims([[1, 2, 3], [4, 5, 6]]);
+---------------------------------+
| array_dims(List([1,2,3,4,5,6])) |
+---------------------------------+
| [2, 3]                          |
+---------------------------------+
```

#### Aliases

- list_dims

### `array_distance`

Returns the Euclidean distance between two input arrays of equal length.

```
array_distance(array1, array2)
```

#### Arguments

- **array1**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **array2**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_distance([1, 2], [1, 4]);
+------------------------------------+
| array_distance(List([1,2], [1,4])) |
+------------------------------------+
| 2.0                                |
+------------------------------------+
```

#### Aliases

- list_distance

### `array_distinct`

Returns distinct values from the array after removing duplicates.

```
array_distinct(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_distinct([1, 3, 2, 3, 1, 2, 4]);
+---------------------------------+
| array_distinct(List([1,2,3,4])) |
+---------------------------------+
| [1, 2, 3, 4]                    |
+---------------------------------+
```

#### Aliases

- list_distinct

### `array_element`

Extracts the element with the index n from the array.

```
array_element(array, index)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **index**: Index to extract the element from the array.

#### Example

```sql
> select array_element([1, 2, 3, 4], 3);
+-----------------------------------------+
| array_element(List([1,2,3,4]),Int64(3)) |
+-----------------------------------------+
| 3                                       |
+-----------------------------------------+
```

#### Aliases

- array_extract
- list_element
- list_extract

### `array_empty`

_Alias of [empty](#empty)._

### `array_except`

Returns an array of the elements that appear in the first array but not in the second.

```
array_except(array1, array2)
```

#### Arguments

- **array1**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **array2**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_except([1, 2, 3, 4], [5, 6, 3, 4]);
+----------------------------------------------------+
| array_except([1, 2, 3, 4], [5, 6, 3, 4]);           |
+----------------------------------------------------+
| [1, 2]                                              |
+----------------------------------------------------+
> select array_except([1, 2, 3, 4], [3, 4, 5, 6]);
+----------------------------------------------------+
| array_except([1, 2, 3, 4], [3, 4, 5, 6]);           |
+----------------------------------------------------+
| [1, 2]                                              |
+----------------------------------------------------+
```

#### Aliases

- list_except

### `array_extract`

_Alias of [array_element](#array_element)._

### `array_has`

Returns true if the array contains the element.

```
array_has(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Scalar or Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_has([1, 2, 3], 2);
+-----------------------------+
| array_has(List([1,2,3]), 2) |
+-----------------------------+
| true                        |
+-----------------------------+
```

#### Aliases

- list_has
- array_contains
- list_contains

### `array_has_all`

Returns true if the array contains the element.

```
array_has(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Scalar or Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_has([1, 2, 3], 2);
+-----------------------------+
| array_has(List([1,2,3]), 2) |
+-----------------------------+
| true                        |
+-----------------------------+
```

#### Aliases

- list_has_all

### `array_has_any`

Returns true if the array contains the element.

```
array_has(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Scalar or Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_has([1, 2, 3], 2);
+-----------------------------+
| array_has(List([1,2,3]), 2) |
+-----------------------------+
| true                        |
+-----------------------------+
```

#### Aliases

- list_has_any

### `array_indexof`

_Alias of [array_position](#array_position)._

### `array_intersect`

Returns distinct values from the array after removing duplicates.

```
array_distinct(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_distinct([1, 3, 2, 3, 1, 2, 4]);
+---------------------------------+
| array_distinct(List([1,2,3,4])) |
+---------------------------------+
| [1, 2, 3, 4]                    |
+---------------------------------+
```

#### Aliases

- list_intersect

### `array_join`

_Alias of [array_to_string](#array_to_string)._

### `array_length`

Returns the length of the array dimension.

```
array_length(array, dimension)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **dimension**: Array dimension.

#### Example

```sql
> select array_length([1, 2, 3, 4, 5], 1);
+-------------------------------------------+
| array_length(List([1,2,3,4,5]), 1)        |
+-------------------------------------------+
| 5                                         |
+-------------------------------------------+
```

#### Aliases

- list_length

### `array_ndims`

Returns an array of the array's dimensions.

```
array_dims(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_dims([[1, 2, 3], [4, 5, 6]]);
+---------------------------------+
| array_dims(List([1,2,3,4,5,6])) |
+---------------------------------+
| [2, 3]                          |
+---------------------------------+
```

#### Aliases

- list_ndims

### `array_pop_back`

Extracts the element with the index n from the array.

```
array_element(array, index)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **index**: Index to extract the element from the array.

#### Example

```sql
> select array_element([1, 2, 3, 4], 3);
+-----------------------------------------+
| array_element(List([1,2,3,4]),Int64(3)) |
+-----------------------------------------+
| 3                                       |
+-----------------------------------------+
```

#### Aliases

- list_pop_back

### `array_pop_front`

Extracts the element with the index n from the array.

```
array_element(array, index)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **index**: Index to extract the element from the array.

#### Example

```sql
> select array_element([1, 2, 3, 4], 3);
+-----------------------------------------+
| array_element(List([1,2,3,4]),Int64(3)) |
+-----------------------------------------+
| 3                                       |
+-----------------------------------------+
```

#### Aliases

- list_pop_front

### `array_position`

Returns the position of the first occurrence of the specified element in the array.

```
array_position(array, element)
array_position(array, element, index)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to search for position in the array.
- **index**: Index at which to start searching.

#### Example

```sql
> select array_position([1, 2, 2, 3, 1, 4], 2);
+----------------------------------------------+
| array_position(List([1,2,2,3,1,4]),Int64(2)) |
+----------------------------------------------+
| 2                                            |
+----------------------------------------------+
> select array_position([1, 2, 2, 3, 1, 4], 2, 3);
+----------------------------------------------------+
| array_position(List([1,2,2,3,1,4]),Int64(2), Int64(3)) |
+----------------------------------------------------+
| 3                                                  |
+----------------------------------------------------+
```

#### Aliases

- list_position
- array_indexof
- list_indexof

### `array_positions`

Returns the position of the first occurrence of the specified element in the array.

```
array_position(array, element)
array_position(array, element, index)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to search for position in the array.
- **index**: Index at which to start searching.

#### Example

```sql
> select array_position([1, 2, 2, 3, 1, 4], 2);
+----------------------------------------------+
| array_position(List([1,2,2,3,1,4]),Int64(2)) |
+----------------------------------------------+
| 2                                            |
+----------------------------------------------+
> select array_position([1, 2, 2, 3, 1, 4], 2, 3);
+----------------------------------------------------+
| array_position(List([1,2,2,3,1,4]),Int64(2), Int64(3)) |
+----------------------------------------------------+
| 3                                                  |
+----------------------------------------------------+
```

#### Aliases

- list_positions

### `array_prepend`

Appends an element to the end of an array.

```
array_append(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to append to the array.

#### Example

```sql
> select array_append([1, 2, 3], 4);
+--------------------------------------+
| array_append(List([1,2,3]),Int64(4)) |
+--------------------------------------+
| [1, 2, 3, 4]                         |
+--------------------------------------+
```

#### Aliases

- list_prepend
- array_push_front
- list_push_front

### `array_push_back`

_Alias of [array_append](#array_append)._

### `array_push_front`

_Alias of [array_prepend](#array_prepend)._

### `array_remove`

Removes the first element from the array equal to the given value.

```
array_remove(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to be removed from the array.

#### Example

```sql
> select array_remove([1, 2, 2, 3, 2, 1, 4], 2);
+----------------------------------------------+
| array_remove(List([1,2,2,3,2,1,4]),Int64(2)) |
+----------------------------------------------+
| [1, 2, 3, 2, 1, 4]                           |
+----------------------------------------------+
```

#### Aliases

- list_remove

### `array_remove_all`

Removes the first element from the array equal to the given value.

```
array_remove(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to be removed from the array.

#### Example

```sql
> select array_remove([1, 2, 2, 3, 2, 1, 4], 2);
+----------------------------------------------+
| array_remove(List([1,2,2,3,2,1,4]),Int64(2)) |
+----------------------------------------------+
| [1, 2, 3, 2, 1, 4]                           |
+----------------------------------------------+
```

#### Aliases

- list_remove_all

### `array_remove_n`

Removes the first element from the array equal to the given value.

```
array_remove(array, element)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **element**: Element to be removed from the array.

#### Example

```sql
> select array_remove([1, 2, 2, 3, 2, 1, 4], 2);
+----------------------------------------------+
| array_remove(List([1,2,2,3,2,1,4]),Int64(2)) |
+----------------------------------------------+
| [1, 2, 3, 2, 1, 4]                           |
+----------------------------------------------+
```

#### Aliases

- list_remove_n

### `array_repeat`

Returns an array containing element `count` times.

```
array_repeat(element, count)
```

#### Arguments

- **element**: Element expression. Can be a constant, column, or function, and any combination of array operators.
- **count**: Value of how many times to repeat the element.

#### Example

```sql
> select array_repeat(1, 3);
+---------------------------------+
| array_repeat(Int64(1),Int64(3)) |
+---------------------------------+
| [1, 1, 1]                       |
+---------------------------------+
> select array_repeat([1, 2], 2);
+------------------------------------+
| array_repeat(List([1,2]),Int64(2)) |
+------------------------------------+
| [[1, 2], [1, 2]]                   |
+------------------------------------+
```

#### Aliases

- list_repeat

### `array_replace`

Replaces the first `max` occurrences of the specified element with another specified element.

```
array_replace_n(array, from, to, max)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **from**: Initial element.
- **to**: Final element.
- **max**: Number of first occurrences to replace.

#### Example

```sql
> select array_replace_n([1, 2, 2, 3, 2, 1, 4], 2, 5, 2);
+-------------------------------------------------------------------+
| array_replace_n(List([1,2,2,3,2,1,4]),Int64(2),Int64(5),Int64(2)) |
+-------------------------------------------------------------------+
| [1, 5, 5, 3, 2, 1, 4]                                             |
+-------------------------------------------------------------------+
```

#### Aliases

- list_replace

### `array_replace_all`

Replaces the first `max` occurrences of the specified element with another specified element.

```
array_replace_n(array, from, to, max)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **from**: Initial element.
- **to**: Final element.
- **max**: Number of first occurrences to replace.

#### Example

```sql
> select array_replace_n([1, 2, 2, 3, 2, 1, 4], 2, 5, 2);
+-------------------------------------------------------------------+
| array_replace_n(List([1,2,2,3,2,1,4]),Int64(2),Int64(5),Int64(2)) |
+-------------------------------------------------------------------+
| [1, 5, 5, 3, 2, 1, 4]                                             |
+-------------------------------------------------------------------+
```

#### Aliases

- list_replace_all

### `array_replace_n`

Replaces the first `max` occurrences of the specified element with another specified element.

```
array_replace_n(array, from, to, max)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **from**: Initial element.
- **to**: Final element.
- **max**: Number of first occurrences to replace.

#### Example

```sql
> select array_replace_n([1, 2, 2, 3, 2, 1, 4], 2, 5, 2);
+-------------------------------------------------------------------+
| array_replace_n(List([1,2,2,3,2,1,4]),Int64(2),Int64(5),Int64(2)) |
+-------------------------------------------------------------------+
| [1, 5, 5, 3, 2, 1, 4]                                             |
+-------------------------------------------------------------------+
```

#### Aliases

- list_replace_n

### `array_resize`

Resizes the list to contain size elements. Initializes new elements with value or empty if value is not set.

```
array_resize(array, size, value)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **size**: New size of given array.
- **value**: Defines new elements' value or empty if value is not set.

#### Example

```sql
> select array_resize([1, 2, 3], 5, 0);
+-------------------------------------+
| array_resize(List([1,2,3],5,0))     |
+-------------------------------------+
| [1, 2, 3, 0, 0]                     |
+-------------------------------------+
```

#### Aliases

- list_resize

### `array_reverse`

Returns the array with the order of the elements reversed.

```
array_reverse(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_reverse([1, 2, 3, 4]);
+------------------------------------------------------------+
| array_reverse(List([1, 2, 3, 4]))                          |
+------------------------------------------------------------+
| [4, 3, 2, 1]                                               |
+------------------------------------------------------------+
```

#### Aliases

- list_reverse

### `array_slice`

Extracts the element with the index n from the array.

```
array_element(array, index)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **index**: Index to extract the element from the array.

#### Example

```sql
> select array_element([1, 2, 3, 4], 3);
+-----------------------------------------+
| array_element(List([1,2,3,4]),Int64(3)) |
+-----------------------------------------+
| 3                                       |
+-----------------------------------------+
```

#### Aliases

- list_slice

### `array_sort`

Sort array.

```
array_sort(array, desc, nulls_first)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **desc**: Whether to sort in descending order(`ASC` or `DESC`).
- **nulls_first**: Whether to sort nulls first(`NULLS FIRST` or `NULLS LAST`).

#### Example

```sql
> select array_sort([3, 1, 2]);
+-----------------------------+
| array_sort(List([3,1,2]))   |
+-----------------------------+
| [1, 2, 3]                   |
+-----------------------------+
```

#### Aliases

- list_sort

### `array_to_string`

Converts each element to its text representation.

```
array_to_string(array, delimiter)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **delimiter**: Array element separator.

#### Example

```sql
> select array_to_string([[1, 2, 3, 4], [5, 6, 7, 8]], ',');
+----------------------------------------------------+
| array_to_string(List([1,2,3,4,5,6,7,8]),Utf8(",")) |
+----------------------------------------------------+
| 1,2,3,4,5,6,7,8                                    |
+----------------------------------------------------+
```

#### Aliases

- list_to_string
- array_join
- list_join

### `array_union`

Returns distinct values from the array after removing duplicates.

```
array_distinct(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select array_distinct([1, 3, 2, 3, 1, 2, 4]);
+---------------------------------+
| array_distinct(List([1,2,3,4])) |
+---------------------------------+
| [1, 2, 3, 4]                    |
+---------------------------------+
```

#### Aliases

- list_union

### `cardinality`

Returns the total number of elements in the array.

```
cardinality(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select cardinality([[1, 2, 3, 4], [5, 6, 7, 8]]);
+--------------------------------------+
| cardinality(List([1,2,3,4,5,6,7,8])) |
+--------------------------------------+
| 8                                    |
+--------------------------------------+
```

### `empty`

Returns 1 for an empty array or 0 for a non-empty array.

```
empty(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select empty([1]);
+------------------+
| empty(List([1])) |
+------------------+
| 0                |
+------------------+
```

#### Aliases

- array_empty
- list_empty

### `flatten`

Converts an array of arrays to a flat array.

- Applies to any depth of nested arrays
- Does not change arrays that are already flat

The flattened array contains all the elements from all source arrays.

```
flatten(array)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.

#### Example

```sql
> select flatten([[1, 2], [3, 4]]);
+------------------------------+
| flatten(List([1,2], [3,4]))  |
+------------------------------+
| [1, 2, 3, 4]                 |
+------------------------------+
```

### `generate_series`

Returns an Arrow array between start and stop with step. The range start..end contains all values with start <= x < end. It is empty if start >= end. Step cannot be 0.

```
range(start, stop, step)
```

#### Arguments

- **start**: Start of the range. Ints, timestamps, dates or string types that can be coerced to Date32 are supported.
- **end**: End of the range (not included). Type must be the same as start.
- **step**: Increase by step (cannot be 0). Steps less than a day are supported only for timestamp ranges.

#### Example

```sql
> select range(2, 10, 3);
+-----------------------------------+
| range(Int64(2),Int64(10),Int64(3))|
+-----------------------------------+
| [2, 5, 8]                         |
+-----------------------------------+

> select range(DATE '1992-09-01', DATE '1993-03-01', INTERVAL '1' MONTH);
+--------------------------------------------------------------+
| range(DATE '1992-09-01', DATE '1993-03-01', INTERVAL '1' MONTH) |
+--------------------------------------------------------------+
| [1992-09-01, 1992-10-01, 1992-11-01, 1992-12-01, 1993-01-01, 1993-02-01] |
+--------------------------------------------------------------+
```

### `list_any_value`

_Alias of [array_any_value](#array_any_value)._

### `list_append`

_Alias of [array_append](#array_append)._

### `list_cat`

_Alias of [array_concat](#array_concat)._

### `list_concat`

_Alias of [array_concat](#array_concat)._

### `list_contains`

_Alias of [array_has](#array_has)._

### `list_dims`

_Alias of [array_dims](#array_dims)._

### `list_distance`

_Alias of [array_distance](#array_distance)._

### `list_distinct`

_Alias of [array_distinct](#array_distinct)._

### `list_element`

_Alias of [array_element](#array_element)._

### `list_empty`

_Alias of [empty](#empty)._

### `list_except`

_Alias of [array_except](#array_except)._

### `list_extract`

_Alias of [array_element](#array_element)._

### `list_has`

_Alias of [array_has](#array_has)._

### `list_has_all`

_Alias of [array_has_all](#array_has_all)._

### `list_has_any`

_Alias of [array_has_any](#array_has_any)._

### `list_indexof`

_Alias of [array_position](#array_position)._

### `list_intersect`

_Alias of [array_intersect](#array_intersect)._

### `list_join`

_Alias of [array_to_string](#array_to_string)._

### `list_length`

_Alias of [array_length](#array_length)._

### `list_ndims`

_Alias of [array_ndims](#array_ndims)._

### `list_pop_back`

_Alias of [array_pop_back](#array_pop_back)._

### `list_pop_front`

_Alias of [array_pop_front](#array_pop_front)._

### `list_position`

_Alias of [array_position](#array_position)._

### `list_positions`

_Alias of [array_positions](#array_positions)._

### `list_prepend`

_Alias of [array_prepend](#array_prepend)._

### `list_push_back`

_Alias of [array_append](#array_append)._

### `list_push_front`

_Alias of [array_prepend](#array_prepend)._

### `list_remove`

_Alias of [array_remove](#array_remove)._

### `list_remove_all`

_Alias of [array_remove_all](#array_remove_all)._

### `list_remove_n`

_Alias of [array_remove_n](#array_remove_n)._

### `list_repeat`

_Alias of [array_repeat](#array_repeat)._

### `list_replace`

_Alias of [array_replace](#array_replace)._

### `list_replace_all`

_Alias of [array_replace_all](#array_replace_all)._

### `list_replace_n`

_Alias of [array_replace_n](#array_replace_n)._

### `list_resize`

_Alias of [array_resize](#array_resize)._

### `list_reverse`

_Alias of [array_reverse](#array_reverse)._

### `list_slice`

_Alias of [array_slice](#array_slice)._

### `list_sort`

_Alias of [array_sort](#array_sort)._

### `list_to_string`

_Alias of [array_to_string](#array_to_string)._

### `list_union`

_Alias of [array_union](#array_union)._

### `make_array`

Returns an array using the specified input expressions.

```
make_array(expression1[, ..., expression_n])
```

#### Arguments

- **expression_n**: Expression to include in the output array. Can be a constant, column, or function, and any combination of arithmetic or string operators.

#### Example

```sql
> select make_array(1, 2, 3, 4, 5);
+----------------------------------------------------------+
| make_array(Int64(1),Int64(2),Int64(3),Int64(4),Int64(5)) |
+----------------------------------------------------------+
| [1, 2, 3, 4, 5]                                          |
+----------------------------------------------------------+
```

#### Aliases

- make_list

### `make_list`

_Alias of [make_array](#make_array)._

### `range`

Returns an Arrow array between start and stop with step. The range start..end contains all values with start <= x < end. It is empty if start >= end. Step cannot be 0.

```
range(start, stop, step)
```

#### Arguments

- **start**: Start of the range. Ints, timestamps, dates or string types that can be coerced to Date32 are supported.
- **end**: End of the range (not included). Type must be the same as start.
- **step**: Increase by step (cannot be 0). Steps less than a day are supported only for timestamp ranges.

#### Example

```sql
> select range(2, 10, 3);
+-----------------------------------+
| range(Int64(2),Int64(10),Int64(3))|
+-----------------------------------+
| [2, 5, 8]                         |
+-----------------------------------+

> select range(DATE '1992-09-01', DATE '1993-03-01', INTERVAL '1' MONTH);
+--------------------------------------------------------------+
| range(DATE '1992-09-01', DATE '1993-03-01', INTERVAL '1' MONTH) |
+--------------------------------------------------------------+
| [1992-09-01, 1992-10-01, 1992-11-01, 1992-12-01, 1993-01-01, 1993-02-01] |
+--------------------------------------------------------------+
```

### `string_to_array`

Converts each element to its text representation.

```
array_to_string(array, delimiter)
```

#### Arguments

- **array**: Array expression. Can be a constant, column, or function, and any combination of array operators.
- **delimiter**: Array element separator.

#### Example

```sql
> select array_to_string([[1, 2, 3, 4], [5, 6, 7, 8]], ',');
+----------------------------------------------------+
| array_to_string(List([1,2,3,4,5,6,7,8]),Utf8(",")) |
+----------------------------------------------------+
| 1,2,3,4,5,6,7,8                                    |
+----------------------------------------------------+
```

#### Aliases

- string_to_list

### `string_to_list`

_Alias of [string_to_array](#string_to_array)._

## Struct Functions

- [named_struct](#named_struct)
- [row](#row)
- [struct](#struct)

### `named_struct`

Returns an Arrow struct using the specified name and input expressions pairs.

```
named_struct(expression1_name, expression1_input[, ..., expression_n_name, expression_n_input])
```

#### Arguments

- **expression_n_name**: Name of the column field. Must be a constant string.
- **expression_n_input**: Expression to include in the output struct. Can be a constant, column, or function, and any combination of arithmetic or string operators.

#### Example

For example, this query converts two columns `a` and `b` to a single column with
a struct type of fields `field_a` and `field_b`:

```sql
> select * from t;
+---+---+
| a | b |
+---+---+
| 1 | 2 |
| 3 | 4 |
+---+---+
> select named_struct('field_a', a, 'field_b', b) from t;
+-------------------------------------------------------+
| named_struct(Utf8("field_a"),t.a,Utf8("field_b"),t.b) |
+-------------------------------------------------------+
| {field_a: 1, field_b: 2}                              |
| {field_a: 3, field_b: 4}                              |
+-------------------------------------------------------+
```

### `row`

_Alias of [struct](#struct)._

### `struct`

Returns an Arrow struct using the specified input expressions optionally named.
Fields in the returned struct use the optional name or the `cN` naming convention.
For example: `c0`, `c1`, `c2`, etc.

```
struct(expression1[, ..., expression_n])
```

#### Arguments

- **expression1, expression_n**: Expression to include in the output struct. Can be a constant, column, or function, any combination of arithmetic or string operators.

#### Example

For example, this query converts two columns `a` and `b` to a single column with
a struct type of fields `field_a` and `c1`:

```sql
> select * from t;
+---+---+
| a | b |
+---+---+
| 1 | 2 |
| 3 | 4 |
+---+---+

-- use default names `c0`, `c1`
> select struct(a, b) from t;
+-----------------+
| struct(t.a,t.b) |
+-----------------+
| {c0: 1, c1: 2}  |
| {c0: 3, c1: 4}  |
+-----------------+

-- name the first field `field_a`
select struct(a as field_a, b) from t;
+--------------------------------------------------+
| named_struct(Utf8("field_a"),t.a,Utf8("c1"),t.b) |
+--------------------------------------------------+
| {field_a: 1, c1: 2}                              |
| {field_a: 3, c1: 4}                              |
+--------------------------------------------------+
```

#### Aliases

- row

## Hashing Functions

- [digest](#digest)
- [md5](#md5)
- [sha224](#sha224)
- [sha256](#sha256)
- [sha384](#sha384)
- [sha512](#sha512)

### `digest`

Computes the binary hash of an expression using the specified algorithm.

```
digest(expression, algorithm)
```

#### Arguments

- **expression**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.
- **algorithm**: String expression specifying algorithm to use. Must be one of:
- md5
- sha224
- sha256
- sha384
- sha512
- blake2s
- blake2b
- blake3

#### Example

```sql
> select digest('foo', 'sha256');
+------------------------------------------+
| digest(Utf8("foo"), Utf8("sha256"))      |
+------------------------------------------+
| <binary_hash_result>                     |
+------------------------------------------+
```

### `md5`

Computes an MD5 128-bit checksum for a string expression.

```
md5(expression)
```

#### Arguments

- **expression**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select md5('foo');
+-------------------------------------+
| md5(Utf8("foo"))                    |
+-------------------------------------+
| <md5_checksum_result>               |
+-------------------------------------+
```

### `sha224`

Computes the SHA-224 hash of a binary string.

```
sha224(expression)
```

#### Arguments

- **expression**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select sha224('foo');
+------------------------------------------+
| sha224(Utf8("foo"))                      |
+------------------------------------------+
| <sha224_hash_result>                     |
+------------------------------------------+
```

### `sha256`

Computes the SHA-256 hash of a binary string.

```
sha256(expression)
```

#### Arguments

- **expression**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select sha256('foo');
+--------------------------------------+
| sha256(Utf8("foo"))                  |
+--------------------------------------+
| <sha256_hash_result>                 |
+--------------------------------------+
```

### `sha384`

Computes the SHA-384 hash of a binary string.

```
sha384(expression)
```

#### Arguments

- **expression**: String expression to operate on. Can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select sha384('foo');
+-----------------------------------------+
| sha384(Utf8("foo"))                     |
+-----------------------------------------+
| <sha384_hash_result>                    |
+-----------------------------------------+
```

### `sha512`

Computes the SHA-512 hash of a binary string.

```
sha512(expression)
```

#### Arguments

- **expression**: String

#### Example

```sql
> select sha512('foo');
+-------------------------------------------+
| sha512(Utf8("foo"))                       |
+-------------------------------------------+
| <sha512_hash_result>                      |
+-------------------------------------------+
```

## Other Functions

- [arrow_cast](#arrow_cast)
- [arrow_typeof](#arrow_typeof)
- [get_field](#get_field)
- [version](#version)

### `arrow_cast`

Casts a value to a specific Arrow data type.

```
arrow_cast(expression, datatype)
```

#### Arguments

- **expression**: Expression to cast. The expression can be a constant, column, or function, and any combination of operators.
- **datatype**: [Arrow data type](https://docs.rs/arrow/latest/arrow/datatypes/enum.DataType.html) name to cast to, as a string. The format is the same as that returned by [`arrow_typeof`]

#### Example

```sql
> select arrow_cast(-5, 'Int8') as a,
  arrow_cast('foo', 'Dictionary(Int32, Utf8)') as b,
  arrow_cast('bar', 'LargeUtf8') as c,
  arrow_cast('2023-01-02T12:53:02', 'Timestamp(Microsecond, Some("+08:00"))') as d
  ;
+----+-----+-----+---------------------------+
| a  | b   | c   | d                         |
+----+-----+-----+---------------------------+
| -5 | foo | bar | 2023-01-02T12:53:02+08:00 |
+----+-----+-----+---------------------------+
```

### `arrow_typeof`

Returns the name of the underlying [Arrow data type](https://docs.rs/arrow/latest/arrow/datatypes/enum.DataType.html) of the expression.

```
arrow_typeof(expression)
```

#### Arguments

- **expression**: Expression to evaluate. The expression can be a constant, column, or function, and any combination of operators.

#### Example

```sql
> select arrow_typeof('foo'), arrow_typeof(1);
+---------------------------+------------------------+
| arrow_typeof(Utf8("foo")) | arrow_typeof(Int64(1)) |
+---------------------------+------------------------+
| Utf8                      | Int64                  |
+---------------------------+------------------------+
```

### `get_field`

Returns a field within a map or a struct with the given key.
Note: most users invoke `get_field` indirectly via field access
syntax such as `my_struct_col['field_name']` which results in a call to
`get_field(my_struct_col, 'field_name')`.

```
get_field(expression1, expression2)
```

#### Arguments

- **expression1**: The map or struct to retrieve a field for.
- **expression2**: The field name in the map or struct to retrieve data for. Must evaluate to a string.

#### Example

```sql
> create table t (idx varchar, v varchar) as values ('data','fusion'), ('apache', 'arrow');
> select struct(idx, v) from t as c;
+-------------------------+
| struct(c.idx,c.v)       |
+-------------------------+
| {c0: data, c1: fusion}  |
| {c0: apache, c1: arrow} |
+-------------------------+
> select get_field((select struct(idx, v) from t), 'c0');
+-----------------------+
| struct(t.idx,t.v)[c0] |
+-----------------------+
| data                  |
| apache                |
+-----------------------+
> select get_field((select struct(idx, v) from t), 'c1');
+-----------------------+
| struct(t.idx,t.v)[c1] |
+-----------------------+
| fusion                |
| arrow                 |
+-----------------------+
```

### `version`

Returns the version of DataFusion.

```
version()
```

#### Example

```sql
> select version();
+--------------------------------------------+
| version()                                  |
+--------------------------------------------+
| Apache DataFusion 42.0.0, aarch64 on macos |
+--------------------------------------------+
```