title: Constraint for one-to-many relationship
body: <p>We have a two tables with a one-to-many relationship.  We would like to enforce a constraint that at least one child record exist for a given parent record.  </p>
  
  <p>Is this possible?  </p>
  
  <p>If not, would you change the schema a bit more complex to support such a constraint?  If so how would you do it?</p>
  
  <p>Edit: I'm using SQL Server 2005</p>