title: Cannot drop index because of foreign key constraint enforcement
body: <p>I can't drop an index because some tables used it for foreign key</p>
  <blockquote>
  <p>Msg 3723, Level 16, State 6, Line 1 An explicit DROP INDEX is not
  allowed on index 'tbl1.ix_cox'. It is being used for FOREIGN KEY
  constraint enforcement.</p>
  </blockquote>
  <p>I tried to disable the index first before dropping</p>
  <pre><code>ALTER INDEX ix_cox On tbl1
  DISABLE
  Go
  </code></pre>
  <p>But still don't able to drop it.</p>
  <p>Do I really need to remove the foreign key on those tables that used that index? Because it is about 30 tables.</p>