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> Reference material for VECTOR_EUCLIDEAN_DISTANCE function

# VECTOR_EUCLIDEAN_DISTANCE

## VECTOR\_EUCLIDEAN\_DISTANCE

Returns the Euclidean distance, or L2 distance, between two vectors. The Euclidean distance measures the shortest distance between two points in space along a straight line. It is calculated by summing the squared distances of a pair of vector elements, and then taking the square root.

**Alias:** `l2_distance` (aligned with pgvector for compatibility)

## Syntax

```sql theme={"theme":{"light":"css-variables","dark":"css-variables"}}
VECTOR_EUCLIDEAN_DISTANCE(<array>, <array>)
```

## Parameters

| Parameter | Description                                        | Supported input types                                                 |
| :-------- | :------------------------------------------------- | :-------------------------------------------------------------------- |
| `<array>` | The first array used in the distance calculation.  | Any array of [numeric data types](/reference-sql/data-types#numeric). |
| `<array>` | The second array used in the distance calculation. | Any array of [numeric data types](/reference-sql/data-types#numeric). |

## Notes

Both input `array` arguments must have the same number of elements.

## Return Type

`DOUBLE`

## Examples

**Example**

The following code returns the Euclidean distance between two vectors:

<div className="query-window">
  ```
  SELECT VECTOR_EUCLIDEAN_DISTANCE([1, 2], [3, 4]) AS distance;
  ```

  | distance <span>double</span> |
  | :--------------------------- |
  | 2.8284271247461903           |

  <p><span>Rows: 1</span><span>Execution time: 5.23ms</span></p>
</div>