HRESULT GetDBSessionFromDataSource
(
IDBInitialize* pIDBInitialize, // [in]
IOpenRowset** ppIOpenRowset_out // [out]
)
{
IDBCreateSession* pIDBCreateSession;
IOpenRowset* pIOpenRowset;
HRESULT hr;
DumpStatusMsg( "Getting a DBSession object from the data source object...\n" );
assert(pIDBInitialize != NULL);
assert(ppIOpenRowset_out != NULL );
hr = pIDBInitialize->QueryInterface( IID_IDBCreateSession, (void**)&pIDBCreateSession);
if (FAILED(hr))
{
DUMP_ERROR_LINENUMBER();
DumpErrorHResult( hr, "IDBInitialize::QI for IDBCreateSession");
goto error;
}
hr = pIDBCreateSession->CreateSession( NULL, IID_IOpenRowset, (IUnknown**)&pIOpenRowset );
if (FAILED(hr))
{
DUMP_ERROR_LINENUMBER();
DumpErrorHResult( hr, "IDBCreateSession::CreateSession");
goto error;
}
pIDBCreateSession->Release();
pIDBCreateSession = NULL;
// all went well
*ppIOpenRowset_out = pIOpenRowset;
return ResultFromScode( S_OK );
error:
if (pIDBCreateSession)
pIDBCreateSession->Release();
*ppIOpenRowset_out = NULL;
return ResultFromScode( hr );
}
DWORD CTextildb::Open()
{
SetCursor(LoadCursor(NULL,IDC_WAIT));
DWORD dr;
DWORD rc;
HRESULT hr;
IDataInitialize * pIDataInitialize = NULL;
IDBInitialize * pIDBInitialize = NULL;
IDBCreateSession* pIDBCreateSession = NULL;
IUnknown * pUnkSession = NULL;
ICommandText* pICommandText = NULL;
IDBCreateCommand* pICreateCommand = NULL;
char cConnectionStr[500];
strcpy(cConnectionStr,"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=bd1.mdb;Persist Security Info=False");
db_CharToWChar(cConnectionStr);
for(;;)
{
dr = ERR_OLEDBFAIL;
hr = CoCreateInstance(CLSID_MSDAINITIALIZE,NULL,CLSCTX_INPROC_SERVER,IID_IDataInitialize,(VOID **)&pIDataInitialize);
if (hr != S_OK) break;
hr = pIDataInitialize->GetDataSource(NULL,CLSCTX_INPROC_SERVER,(LPCOLESTR)cConnectionStr,IID_IDBInitialize,(IUnknown **)&pIDBInitialize);
if (hr != S_OK) break;
hr = pIDBInitialize->Initialize();
if (hr != S_OK) break;
hr = pIDBInitialize->QueryInterface(IID_IDBCreateSession, (void**)&pIDBCreateSession);
if (hr != S_OK) break;
hr = pIDBCreateSession->CreateSession(NULL,IID_IOpenRowset,&pUnkSession );
if (hr != S_OK) break;
hr = pUnkSession->QueryInterface(IID_IDBCreateCommand,(void**)&pICreateCommand);
if (hr != S_OK) break;
hr = pICreateCommand->CreateCommand(NULL,IID_ICommand,(IUnknown**)&m_lpICommand);
if (hr != S_OK) break;
dr = ERR_NONE;
break;
};
if (pIDataInitialize) rc = pIDataInitialize->Release();
if (pIDBInitialize) rc = pIDBInitialize->Release();
if (pIDBCreateSession) rc = pIDBCreateSession->Release();
if (pUnkSession) rc = pUnkSession->Release();
if (pICreateCommand) rc = pICreateCommand->Release();
if (hr != S_OK)
{
if (m_lpICommand) rc = m_lpICommand->Release();
m_lpICommand = NULL;
}
SetCursor(LoadCursor(NULL,IDC_ARROW));
return ERR_OLEDBFAIL;
}
ICommandText* CClientDB::CreateCommand( IDBInitialize* pIDBInitialize ,LPCWSTR wCmdString )
{
IDBCreateSession* pIDBCreateSession = NULL;
IDBCreateCommand* pIDBCreateCommand = NULL;
ICommandText* pICommandText = NULL;
if( pIDBInitialize == NULL || wCmdString == NULL )
{
return NULL;
}
//Create a new activity from the data source object.
if(FAILED(pIDBInitialize->QueryInterface( IID_IDBCreateSession, (void**) &pIDBCreateSession)))
{
return NULL;
}
if(FAILED(pIDBCreateSession->CreateSession( NULL, IID_IDBCreateCommand, (IUnknown**) &pIDBCreateCommand)))
{
return NULL;
}
pIDBCreateSession->Release();
//Create a Command object.
if(FAILED(pIDBCreateCommand->CreateCommand( NULL, IID_ICommandText, (IUnknown**) &pICommandText)))
{
pIDBCreateCommand->Release();
return NULL;
}
pIDBCreateCommand->Release();
//Set the command text.
if(FAILED(pICommandText->SetCommandText(DBGUID_DBSQL, wCmdString )))
{
pICommandText->Release();
return NULL;
}
return pICommandText;
}