Database

CDatabase * pDatabase = new CDatabase();<br />
pDatabase->OpenEx(); //ask user to select a DSN<br />
<br />
CRecordsetST myRecordset(pDatabase);<br />
myRecordset.Open(AFX_DB_USE_DEFAULT_TYPE, NULL, CRecordset::optimizeBulkAdd | CRecordset::appendOnly);<br />
if(!myRecordset.IsOpen())<br />
{<br />
	pDatabase->Close();<br />
	return;<br />
}<br />
<br />
pDatabase->BeginTrans();<br />
<br />
while( //file is not EOF )<br />
{<br />
	try<br />
	{<br />
		myRecordset.AddNew();<br />
		//fill recordset fields with file data<br />
		//.....<br />
		//.....<br />
		//.....<br />
		//.....<br />
		myRecordset.Update();<br />
	}<br />
	catch(CDBException *e)<br />
	{<br />
		//if a CDBException is catched, then<br />
		//cancelupdate to pass current record<br />
		//and continue to next data without<br />
		//doing rollback<br />
<br />
		//cancel update to prepare next record<br />
		myRecordset.CancelUpdate();<br />
		//trace some message<br />
		OutputDebugString(e->m_strError+_T("\n"));<br />
		e->Delete();<br />
<br />
		//here I do not want to rollback my transaction, but just cancel current update<br />
		//and continue my process with keeping all previously added records (good ones)<br />
	}<br />
	catch(...)<br />
    	{<br />
		//if an unknown exception if catched then rollback all<br />
		myRecordset.CancelUpdate();<br />
		//trace some message<br />
		OutputDebugString(_T("FATAL error while inserting data\n"));<br />
		//perform rollback<br />
		pDatabase->Rollback();<br />
		pDatabase->Close();<br />
		return;<br />
    	}<br />
	//read next line in file<br />
}<br />
<br />
pDatabase->CommitTrans();<br />
pDatabase->Close();<br />
...

SELECT * FROM Orders O1 WHERE exists<br />
(SELECT TOP 1 * from Orders O2 WHERE O1.CustID = O2.CustID AND O1.OrderDate = O2.OrderDate Order by OrderDate)

<br />
Connection.Open();<br />
//Invoke the stored procedure n1<br />
Connection.Close();<br />
<br />
Connection.Open();<br />
//Invoke the stored procedure n2<br />
Connection.Close();<br />
<br />
Connection.Open();<br />
//Invoke the stored procedure n3<br />
Connection.Close();<br />
<br />
Connection.Open();<br />
//Invoke the stored procedure n4<br />
Connection.Close();<br />

<br />
Connection.Open();<br />
<br />
//Invoke the stored procedure n1<br />
<br />
<br />
//Invoke the stored procedure n2<br />
<br />
<br />
//Invoke the stored procedure n3<br />
<br />
<br />
//Invoke the stored procedure n4<br />
<br />
Connection.Close();<br />