title: Check if field contains special character in SQL
body: <p>We decided to use <code>Nvarchar</code> to store some information in some tables, the reason is that we assumed that we will have a lot of special characters since the database contains French and German data.</p>
  
  <p>After extracting some of the data, we estimated the full run to have and extreamlly huge size (20 TB)</p>
  
  <p>Now we would like to check every table to find if there are special characters found, if not then we change the type from <code>NvarChar</code> to <code>Varchar</code></p>
  
  <p>Any idea how can we query this?</p>
  
  <p>or what do you think the best way to optimize the size?</p>