Procedura: Utilizzo delle transazioni con OLE DB (a livello di programmazione)
In questo argomento viene illustrato come utilizzare le transazioni durante la programmazione con il provider OLE DB per SQL Server 2005 Compact Edition (SQL Server Compact Edition).
Esempio
Nell'esempio seguente viene illustrato come creare ed eseguire una transazione utilizzando il provider OLE DB per SQL Server Compact Edition. L'esempio contiene solo le sezioni relative alla transazione della funzione InsertEmployeeInfo.
///////////////////////////////////////////////////////////////////////
// The following steps have been removed from this sample.
// 1) Verify that IDBCreateSession exists on the datasource.
// 2) Create a session object.
// 3) Set up information necessary to open a table by using an index.
// 4) Set the binding properties and create the accessor.
///////////////////////////////////////////////////////////////////////
// Begins a new local transaction to insert employee data
hr = pITxnLocal->StartTransaction(ISOLATIONLEVEL_READCOMMITTED, 0, NULL, NULL);
// Error handling for failed creation of the transaction
if(FAILED(hr))
{
goto Exit;
}
///////////////////////////////////////////////////////////////////////
// The code to prepare the sample data to insert has been removed.
//
///////////////////////////////////////////////////////////////////////
hr = pIRowsetChange->InsertRow(DB_NULL_HCHAPTER, hAccessor, pData, prghRows);
// Error handling that aborts the transaction on failure
if (FAILED(hr))
{
goto Abort;
}
// Get the row data.
hr = pIRowset->GetData(rghRows[0], hAccessor, pData);
if(FAILED(hr))
{
goto Abort;
}
// Check the status.
if (DBSTATUS_S_OK != *(DBSTATUS*)(pData+prgBinding[dwPhotoCol].obStatus))
{
hr = E_FAIL;
pIRowset->ReleaseRows(1, prghRows, NULL, NULL, NULL);
goto Abort;
}
///////////////////////////////////////////////////////////////////////
// Perform a transactional task here.
///////////////////////////////////////////////////////////////////////
// Commit the transaction by using ITransactionLocal::Commit
// to insert the data.
if (pITxnLocal)
{
pITxnLocal->Commit(FALSE, XACTTC_SYNC, 0);
}
goto Exit;
// Calling goto Abort uses the ITransactionLocal::Abort
// to cancel the transaction.
Abort:
// Cancel the transaction.
if (pITxnLocal)
{
pITxnLocal->Abort(NULL, FALSE, FALSE);
}
Exit:
// Release the resources.