# Joined group by

Performs a [group by](../card-group-by/index.md) operation, then joins the result onto the current transform table.  This can be useful for comparison workflows, such as comparing each row against all rows in the specified group.

## Input type

Transform table

## Output type

Transform table

## Usage information

| Functionality | Availability |
| --- | --- |
| [Standard Quiver card](../core-concepts/index.md#cards) | Unsupported |
| [Transform table transform](../cards-transform-table/index.md) | Supported |