# MV_FIRST

The MV_FIRST function converts a multivalued expression into a single-valued column containing the first value. This is especially useful when working with functions that produce multivalued columns in a known order, such as `SPLIT`. The order in which multivalued fields are read from underlying storage is not guaranteed and is frequently ascending, but you should not rely on this. If you need the minimum value, use `MV_MIN` instead, as it is optimized for sorted values and does not offer a performance benefit over `MV_FIRST`.

## Syntax

`MV_FIRST(field)`

### Parameters

#### field

A multivalue expression to extract the first value from.

## Examples

Extracts the first value from a semicolon-separated string by splitting the string and selecting the first element.

```esql
ROW a="foo;bar;baz"
| EVAL first_a = MV_FIRST(SPLIT(a, ";"))
```
