title: How to add new JSON column in Postgres
body: <p>I am trying to add a json type column to the table, but it doesn’t work and I cannot get normal examples, what am I doing wrong?</p>
  
  <pre><code>ALTER TABLE user ADD COLUMN purshased_product SET DATA TYPE JSONB USING purshased_product::JSONB;
  </code></pre>
  
  <p>I'm not trying to change the column, but just create a new one with json type</p>
  
  <pre><code>@Convert(converter = PurshasedProductConverter.class)
  private PurshasedProductConverter[] purshasedProducts;
  </code></pre>
  
  <p>my variable</p>