title: Which variable type to use when using text as primary key in SQL Server database
body: <p>I am aware about pros and cons of using a text as primary key in table<br>
  (there is <a href="https://stackoverflow.com/questions/517579/strings-as-primary-keys-in-sql-database">discussion</a>).</p>
  
  <p>However I just wonder if I must use <code>varchar(10)</code> or <code>char(10)</code> or other  </p>
  
  <p>Values will look like 1-115115151  (length may differ)</p>