# Create arrays from subqueries
<a name="creating-arrays-from-subqueries"></a>

Create an array from a collection of rows.

```
WITH
dataset AS (
  SELECT ARRAY[1,2,3,4,5] AS items
)
SELECT array_agg(i) AS array_items
FROM dataset
CROSS JOIN UNNEST(items) AS t(i)
```

This query returns:

```
+-----------------+
| array_items     |
+-----------------+
| [1, 2, 3, 4, 5] |
+-----------------+
```

To create an array of unique values from a set of rows, use the `distinct` keyword.

```
WITH
dataset AS (
  SELECT ARRAY [1,2,2,3,3,4,5] AS items
)
SELECT array_agg(distinct i) AS array_items
FROM dataset
CROSS JOIN UNNEST(items) AS t(i)
```

This query returns the following result. Note that ordering is not guaranteed.

```
+-----------------+
| array_items     |
+-----------------+
| [1, 2, 3, 4, 5] |
+-----------------+
```

For more information about using the `array_agg` function, see [Aggregate functions](https://trino.io/docs/current/functions/aggregate.html) in the Trino documentation.