title: Does primary key datatype affect performance? SQL Server 2008
body: <p>Is there a performance hit if you use one data type for your primary key versus another?  </p>
  
  <p>I have a large database that will be queried often, but only written to once a year. Will it matter at all if I supply an incremental primary key (integer) or let SQL Server give it a GUID?</p>