title: Google Sheet Query - Group / concatenate multiple rows
body: <p>I'm running a <code>QUERY</code> with a <code>SUM</code> and <code>GROUP BY</code>, but I'd like to aggregate multiple distinct values from the rows into a single row and column. I'm looking to concatenate all those values together.</p>
  <p><strong>Current Table:</strong></p>
  <div class="s-table-container">
  <table class="s-table">
  <thead>
  <tr>
  <th>Person</th>
  <th>Widget</th>
  <th>Count</th>
  </tr>
  </thead>
  <tbody>
  <tr>
  <td>Bill</td>
  <td>Red</td>
  <td>12</td>
  </tr>
  <tr>
  <td>Bill</td>
  <td>Blue</td>
  <td>9</td>
  </tr>
  <tr>
  <td>Sarah</td>
  <td>Yellow</td>
  <td>4</td>
  </tr>
  <tr>
  <td>Bill</td>
  <td>Yellow</td>
  <td>1</td>
  </tr>
  <tr>
  <td>Sarah</td>
  <td>Orange</td>
  <td>10</td>
  </tr>
  </tbody>
  </table>
  </div>
  <p><strong>Expected Table</strong>:</p>
  <div class="s-table-container">
  <table class="s-table">
  <thead>
  <tr>
  <th>Person</th>
  <th>Widget</th>
  <th>Count</th>
  </tr>
  </thead>
  <tbody>
  <tr>
  <td>Bill</td>
  <td>Red, Blue, Yellow</td>
  <td>22</td>
  </tr>
  <tr>
  <td>Sarah</td>
  <td>Yellow, Orange</td>
  <td>14</td>
  </tr>
  </tbody>
  </table>
  </div>