An invalid SQLLEN(<num>) was found for a FLOAT field in the
  SQLDA

  Explanation:  You passed in an SQLDA with a SQLTYPE FLOAT SQLLEN
  that was invalid.  Only 4, 8, and 16 are legal floating-point
  lengths.

  User Action:  Set the SQLLEN to 4, 8, or 16, depending on the
  length of the floating-point variable passed.