title: SQL - list all data if a column is empty
body: <p>I'm trying to write a WHERE clause, which returns all data if the column is empty. I have a csv file (static_table) which consists of:</p>
  <p><a href="https://i.stack.imgur.com/jJUp6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jJUp6.png" alt="enter image description here" /></a></p>
  <p>If the permission is empty that means that the user will need to see everything.
  So if the hvfg23 user is logged in and runs a query that has country, region and brand, whenever the query is executed the user can see data for every country, for Europe region and all brands.</p>
  <p>The query I have at the moment looks something like this:</p>
  <pre><code>select * from t1
  where(select restriction, type from t2 where user_id = {{current_userId()}} )
  </code></pre>
  <p>I'm having trouble adjusting the query to what exactly I need, the help will be very appreciated.</p>