function DataTypeToStr(dt: TDataType): String;
begin
  case dt of
    ftUnknown: Result := 'ftUnknown';
    ftString: Result := 'ftString';
    ftSmallint: Result := 'ftSmallint';
    ftInteger: Result := 'ftInteger';
    ftWord: Result := 'ftWord';
    ftBoolean: Result := 'ftBoolean';
    ftFloat: Result := 'ftFloat';
    ftCurrency: Result := 'ftCurrency';
    ftBCD: Result := 'ftBCD';
    ftDate: Result := 'ftDate';
    ftTime: Result := 'ftTime';
    ftDateTime: Result := 'ftDateTime';
    ftBytes: Result := 'ftBytes';
    ftVarBytes: Result := 'ftVarBytes';
    ftAutoInc: Result := 'ftAutoInc';
    ftBlob: Result := 'ftBlob';
    ftMemo: Result := 'ftMemo';
    ftGraphic: Result := 'ftGraphic';
    ftFmtMemo: Result := 'ftFmtMemo';
    ftParadoxOle: Result := 'ftParadoxOle';
    ftDBaseOle: Result := 'ftDBaseOle';
    ftTypedBinary: Result := 'ftTypedBinary';
    ftCursor: Result := 'ftCursor';
    ftFixedChar: Result := 'ftFixedChar';
    ftWideString: Result := 'ftWideString';
    ftLargeint: Result := 'ftLargeint';
    ftADT: Result := 'ftADT';
    ftArray: Result := 'ftArray';
    ftReference: Result := 'ftReference';
    ftDataSet: Result := 'ftDataSet';
    ftOraBlob: Result := 'ftOraBlob';
    ftOraClob: Result := 'ftOraClob';
    ftVariant: Result := 'ftVariant';
    ftInterface: Result := 'ftInterface';
    ftIDispatch: Result := 'ftIDispatch';
    ftGuid: Result := 'ftGuid';
    ftTimeStamp: Result := 'ftTimeStamp';
    ftFMTBcd: Result := 'ftFMTBcd';
  end;
end;