title: Remove (merge) SQL Servers' database secondary data file
body: <p>I have a database backup for which SQL Server Management Studio says that it has three files in it: an <code>.mdf</code> file, an <code>.ndf</code> file and one <code>.ldf</code> file. This secondary data file (the <code>.ndf</code> one) was created for no obvious reason, so I want to remove it altogether (without losing data, of course), preferably during while the database is being restored from the backup.</p>
  
  <p>Is this at all doable?</p>