用getdata if (FAILED(hr = pIAccessor->CreateAccessor(DBACCESSOR_ROWDATA, 1,
        &dbbinding, 0, &haccessor, &ulbindstatus)))
       dwStatus = *((ULONG*) (pRow + dbbinding.obStatus));...
  if (SUCCEEDED(hr = pIRowset->GetData(hRow, haccessor, pRow)))
if (dwStatus == DBSTATUS_S_OK)
            {
            pISequentialStream = *((ISequentialStream**) 
                (pRow + dbbinding.obValue));
hr =  pISequentialStream->Read(pUnboundData,
                    BLOCK_SIZE, &cbRead))