title: Unique constraint on multiple fields in Access 2003
body: <p>I have not found any answer regarding my question, all unique constraint questions did not involve MS Access. </p>
  
  <p>The question is how to make a unique constraint on multpile fields in MS Access 2003 database?</p>
  
  <p>If my table consists of columns <code>id, A, B, C, D, E, F</code>. I have an index on column <strong>id</strong>, but I would like to have a unique constraint set on both columns <code>A</code> and <code>B</code>. Hence, I may have a duplicate value in column <code>A</code>, provided the value in column <code>B</code> are different.</p>
  
  <p>I want to stress that I am <strong>not interested</strong> in a workaround like <strong>creating new column</strong> with concatenated values from columns <code>A</code> and <code>B</code>, and creating a constraint on this column.</p>