> ## Documentation Index
> Fetch the complete documentation index at: https://docs.firebolt.io/llms.txt
> Use this file to discover all available pages before exploring further.

<AgentInstructions>

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

POST https://docs.firebolt.io/feedback

```json
{
  "path": "/reference-sql/functions-reference/conditional-and-miscellaneous/city-hash",
  "feedback": "Description of the issue"
}
```

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</AgentInstructions>

> Reference material for CITY_HASH function

# CITY_HASH

Takes one or more input parameters of any data type and returns a 64-bit non-cryptographic hash value. `CITY_HASH` uses the CityHash algorithm for string data types, implementation-specific algorithms for other data types, and the CityHash combinator to produce the resulting hash value. If any of the inputs is `NULL`, the result will be `NULL`. See [HASH](/reference-sql/functions-reference/conditional-and-miscellaneous/hash) if `NULL` values should not produce `NULL`.

## Syntax

```sql theme={"theme":{"light":"github-light","dark":"github-dark"}}
CITY_HASH(<expression>, [, expression [,...]])
```

## Parameters

| Parameter      | Description                                                      | Supported input types |
| :------------- | :--------------------------------------------------------------- | :-------------------- |
| `<expression>` | An expression that returns any data type that Firebolt supports. | Any                   |

## Return type

`BIGINT`

## Example

```sql theme={"theme":{"light":"github-light","dark":"github-dark"}}
SELECT CITY_HASH('esimpson', '08-25-2016')
```

**Returns:** `-6,509,667,128,195,191,394`

```sql theme={"theme":{"light":"github-light","dark":"github-dark"}}
SELECT CITY_HASH(NULL, '08-25-2016')
```

**Returns:** `NULL`