# Arrays

{% hint style="info" %}
For a full list of array functions see the [SQL Reference](/latest/devx/6.1/user-guide/sql-reference/functions.md#array-functions).
{% endhint %}

### Create an array field <a href="#create-an-array-field" id="create-an-array-field"></a>

You can create array fields using the `..[]` syntax:

```sql
CREATE TABLE table(
    _key INT,
    , fialdA INT[]            -- Simple array
    , fieldB.fieldC STRING[]) -- Array in a subfield
    , fieldD INT[][]          -- Nested array
FORMAT(avro, avro);
```

### Select an array field <a href="#select-an-array-field" id="select-an-array-field"></a>

Tables can store data containing arrays. Here is a SQL statement for querying an array item:

```sql
SELECT
    fieldA[1]
     , fieldB.fieldC[2].x
FROM table
WHERE fieldA[1] LIKE '%Lenses%'
```

When working with arrays is good to check the array bounds. See the `SIZEOF` function in the list of supported functions.

### Query for array size <a href="#query-for-array-size" id="query-for-array-size"></a>

Sometimes you want to find out how many items are in your array. To do so you can run:

```sql
SELECT
    SIZEOF(arrayFieldA)
FROM table
```


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