Number of host variables passed (<num>) does not match number of
  parameters (<num>)

  Explanation:  The number of host variables you passed in to an
  EXECUTE, OPEN, or FETCH statement does not match the number of
  parameter markers (question marks) in the PREPARE statement's
  command string.

  User Action:  Make sure the number of host variables matches the
  number of parameter markers in the PREPARE statement.  There are
  two ways to pass in host variables.  One, explicitly pass in a
  list of host variables in a USING list.  Or two, pass in an
  SQLDA in a USING DESCRIPTOR clause.  If you are using an SQLDA,
  you must specify in the SQLDA SQLN field the number of SQLVAR
  structures you have initialized to point to your variables.