title: PostgreSQL - What should I put inside a JSON column
body: <h3>The data I want to store data that has this characteristics:</h3>
  <ul>
  <li>There are a finite number of fields (I don't expect to add new fields);</li>
  <li>There are some columns that are common to all sets of data (a category field, for instance);</li>
  <li>There are some columns that are specific to individual sets of data (each category needs it's own fields);</li>
  </ul>
  <h3>Here's how it would look like in a regular table:</h3>
  <p><a href="https://i.stack.imgur.com/keCrD.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/keCrD.png" alt="Table" /></a></p>
  <p><strong>I'm having trouble figuring out which would be the better way to store this data in a database for this situation.</strong></p>
  <h3>Bellow are the ideas I already had:</h3>
  <ul>
  <li>Do exactly as the tabular table (I would have many NULL values);</li>
  <li>Divide the categories into tables (I would use joins when needed);</li>
  <li>Use JSON type for storing the values (no NULL values and having it all in same table).</li>
  </ul>
  <h3>So my questions are:</h3>
  <ol>
  <li>Is one of these solutions (or one that I have not thought about it) that is better for this case?</li>
  <li>Are there other factors, other than the ones presented here, that I should consider to make this decision?</li>
  </ol>