title: In SQL Server changing column varchar(255) nvarchar
body: <p>I am using SQL server 2008 express and some of our columns are defined as varchar(255). Should I convert these columns to NvarChar(255) or nvarchar(max)?</p>
  
  <p>The reason I ask is I read that nvarchar(255) for unicode characters would actually store 1/2 the number of characters (since unicode characters are 2 bytes) whereas 255 with varchar() would allow  me to store 255 characters (or is it 255 - 2 for the offset).</p>
  
  <p>Would there be any performance hits using nvarchar(max)?</p>
  
  <p>JDs</p>