ADO入门级问题

Question

void CADOTextDlg::OnConnectDb() 
{
// TODO: Add your control notification handler code here
m_connect.CreateInstance(__uuidof(Connection));
try
{
m_connect->PutConnectionTimeout(10);
_bstr_t connectstr("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=CreateThread.mdb");
m_connect->Open(connectstr,"","",adModeUnknown);
}
catch(_com_error* e)
{
MessageBox(e->ErrorMessage());
}

m_recordset.CreateInstance(__uuidof(Recordset));
try
{
m_recordset->Open("SELECT * FROM first",m_connect.GetInterfacePtr(),adOpenDynamic,adLockOptimistic
,adCmdText);
}
catch(_com_error* e)
{
MessageBox(e->ErrorMessage());
}
}
程序运行到m_recordset->Open时就会出错，问题到底在哪里？？？

Answer 1

_variant_t vCurRecord;
m_recordset =  m_connect->Execute("SELECT * FROM first", &vCurRecord, adCmdText);

Answer 2

m_recordset->Open("SELECT * FROM first",m_connect.GetInterfacePtr(),adOpenDynamic,adLockOptimistic