---
title: ES|QL STARTS_WITH function
description: 
url: https://www.elastic.co/elastic/docs-builder/docs/3028/reference/query-languages/esql/functions-operators/string-functions/starts_with
products:
  - Elasticsearch
---

# ES|QL STARTS_WITH function
## Syntax

![Embedded](https://www.elastic.co/elastic/docs-builder/docs/3028/reference/query-languages/esql/images/functions/starts_with.svg)


## Parameters

<definitions>
  <definition term="str">
    String expression. If `null`, the function returns `null`.
  </definition>
  <definition term="prefix">
    String expression. If `null`, the function returns `null`.
  </definition>
</definitions>


## Description

Returns a boolean that indicates whether a keyword string starts with another string.

## Supported types


| str     | prefix  | result  |
|---------|---------|---------|
| keyword | keyword | boolean |
| keyword | text    | boolean |
| text    | keyword | boolean |
| text    | text    | boolean |


## Example

```esql
FROM employees
| KEEP last_name
| EVAL ln_S = STARTS_WITH(last_name, "B")
```


| last_name:keyword | ln_S:boolean |
|-------------------|--------------|
| Awdeh             | false        |
| Azuma             | false        |
| Baek              | true         |
| Bamford           | true         |
| Bernatsky         | true         |