title: When must we use NVARCHAR/NCHAR instead of VARCHAR/CHAR in SQL Server?
body: <p>Is there a rule when we must use the Unicode types?  </p>
  
  <p>I have seen that most of the European languages (German, Italian, English, ...) are fine in the same database in VARCHAR columns.</p>
  
  <p>I am looking for something like: </p>
  
  <ol>
  <li>If you have Chinese --> use NVARCHAR</li>
  <li>If you have German and Arabic --> use NVARCHAR</li>
  </ol>
  
  <p>What about the collation of the server/database?</p>
  
  <p>I don't want to use always NVARCHAR like suggested here
  <a href="https://stackoverflow.com/questions/35366/varchar-vs-nvarchar-performance">What are the main performance differences between varchar and nvarchar SQL Server data types?</a></p>