title: Split one string with commas into columns
body: <p>For example, I have the following table:</p>
  <pre><code>| Block                       |
  | abcdefgh,12kjkjkj,231wewoxyz|
  </code></pre>
  <p>How can I convert it into:</p>
  <pre><code>| Block1   | Block2   | Block3     |
  | abcdefgh | 12kjkjkj | 231wewoxyz |
  </code></pre>
  <p>Note:</p>
  <ul>
  <li>Each &quot;Block&quot; has a maximum of 8 commas (and hence can be split into 9 smaller blocks). The number of commas varies; some have 8 commas, some have 4, some have 7, etc. Each smaller block will occupy a column.</li>
  </ul>
  <p>I use Presto, btw.</p>