# `ARRAY_TO_STRING`

**Applies to:** ✅ Data 360 SQL ✅ Tableau Hyper API

Converts an array to a string using a separator and an optional null indicator.

## Syntax

```sql
array_to_string(<array>, <separator>[, null_string])
```

## Arguments

### Required

- `<array>`: The array to convert.
- `<separator>`: The delimiter to insert between elements.

### Optional

- `null_string`: The string to use for NULL elements.

## Returns

Returns a text value that contains all array elements joined by the separator. Without the optional `null_string` parameter, NULL elements are omitted from the output.

## Examples

### Basic Conversion

Convert an array to a semicolon-separated string.

```sql
SELECT array_to_string(array[1, 2, 3, NULL], ';') AS result;
```

Returns `'1;2;3'`, joining all elements with semicolons. The `NULL` element was ignored because no `NULL` value was specified.

### Handle NULL Elements

Convert an array with NULL values using a custom null indicator.

```sql
SELECT array_to_string(array[3, 2, 1, null], '-', 'N/A') AS result;
```

Returns `'3-2-1-N/A'`, replacing the NULL element with the specified indicator.

## Related Documentation

- [Array Data Type](/docs/data/data-cloud-query-guide/references/dc-sql-reference/array.md)