# MAXBY

MAXBY(`column`, `partition column` )

Returns the maximum value in a column when grouped by unique values within a `partition column`

{% hint style="info" %}
MAXBY() is a [**window function**](/cascade/functions-and-expressions/building-expressions/guide-to-window-functions.md)**,** which performs MAX() except partitioned by the unique values of a separate column.
{% endhint %}

### Arguments

| Arguments          | Description                     |
| ------------------ | ------------------------------- |
| `column`           | Column to search for maximum    |
| `partition column` | Column containing unique values |

### Output

Outputs the maximum value of a column when grouped by `partition column`

### Example

{% embed url="<https://datawrapper.dwcdn.net/NIeNZ/1/>" %}


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