title: I know this is a circular reference but its difficult for me to understand why this is bad
body: <p>We have a project running where i need to do some ETL work into a new database that created was by a different company.  While going through the database diagram given to me by the developers i saw that there was a circular reference on 4 of the tables:</p>
  
  <p>I can't upload the diagram but here is a general structure of the tables:</p>
  
  <p>CASE</p>
  
  <ul>
  <li>ID (PK) CaseStatusInfo (FK)  </li>
  <li>SignOffPlanning (FK) </li>
  <li>SignOffReportReview (FK)  </li>
  <li>SignOffQuarterlyReview (FK)</li>
  </ul>
  
  <p>CaseStatusInfo</p>
  
  <ul>
  <li>ID (PK)</li>
  <li>CaseId (FK)</li>
  </ul>
  
  <p>SignOffPlanning</p>
  
  <ul>
  <li>ID (PK)</li>
  <li>CaseId (FK)</li>
  </ul>
  
  <p>SignOffReportReview</p>
  
  <ul>
  <li>ID (PK)</li>
  <li>CaseId (FK)</li>
  </ul>
  
  <p>SignOffQuarterlyReview</p>
  
  <ul>
  <li>ID (PK)</li>
  <li>CaseId (FK)</li>
  </ul>
  
  <p>How these Info tables linked to the Case table will be used is that it will be storing historic statuses of a case by having the primary key stored within each Info table.  This really does make logical sense but i feel that it might have been better to normalize these tables even further to keep the historic data in those normalized tables.</p>
  
  <p>My question is:  What problems could arise from having this type of database structure instead of further normalizing the tables?</p>