Inconsistent leaf cardinality (C2) of !@UQ specified
  for entry <num> at dbkey <num>:<num>:<num>  using  precision  of
  <num>.
  Dbkey <num>:<num>:<num> at level <num> specified  a  cardinality
  of !@UQ

  Explanation:   The  cardinality  specified  in   an   entry   is
  inconsistent  with  the the cardinality supplied by the targeted
  child in the b-tree.

  User Action:  Drop the index and rebuild it.