# Scripting functions overview

SurrealDB allows for advanced functions with complicated logic, by allowing embedded functions to be written in JavaScript.

SurrealDB allows for advanced functions with complicated logic, by allowing embedded functions to be written in JavaScript. These functions support the ES2020 JavaScript specification.

## Setup

To allow scripting functions to be used, the `--allow-scripting` flag must be passed in when using the `surreal start` command to start the database.

## Simple function

Embedded JavaScript functions within SurrealDB support all functionality in the ES2020 specification including async / await functions, and generator functions. Any value from SurrealDB is converted into a JavaScript type automatically, and the return value from the JavaScript function is converted to a SurrealDB value.

```surql
CREATE person SET scores = function() {
	return [1,2,3].map(v => v * 10);
};
```

```surql title="Output"
[
	{
		id: person:zju99ptfepm87ylqf2h2,
		scores: [
			10,
			20,
			30
		]
	}
]
```