Another Simple ADO Class

Introduction

Here is another ADO class for any database projects you may have coming up. The class is provided from the link above. The class is zipped up with the ado type library. I created this class because I couldn't find any good ado classes with disconnected recordsets in them. I hope this class helps you out. Here are the main methods:

CRADatabase()
~CRADatabase()
RAConnect(char *ConnectionString)
RAGetDisconnectedRs(char *SqlStatement)
RAExecuteNoRs(char *SqlStatement)
RAExecuteRs(char *SqlStatement)

Usage:

	_RecordsetPtr oRs;
	CRADatabase rad;

	for (int count=0; count<1000; count++)
	{

		if (S_OK == rad.RAConnect("DSN=Database;UID=sa;PWD="))		
		{			
			oRs = rad.RAGetDisconnectedRs("SELECT TOP 100 * FROM orders");
			
			CComVariant val;
			if (oRs)
			{
				while (!oRs->adoEOF)
				{
					val = oRs->Fields->Item[_variant_t("order_number")]->Value;
					if (val.vt != (VT_NULL))
					{
						printf("%s\n",(char*)_bstr_t(val));				
					}
					oRs->MoveNext();
				}
				oRs->Release();					
				oRs->Close();
			}
			
		}
        }

Here is the code (Click on link above to get zipped class!):

// RADatabase.cpp: implementation of the CRADatabase class.

//

//////////////////////////////////////////////////////////////////////


#include "stdafx.h"

#include "RADatabase.h"


//////////////////////////////////////////////////////////////////////

// Construction/Destruction

//////////////////////////////////////////////////////////////////////


CRADatabase::CRADatabase()
{
	try
	{
		// Initialize COM

		CoInitialize(NULL);
		// Initialize ADO

		m_Command.CreateInstance(__uuidof(Command));
		m_Recordset.CreateInstance(__uuidof(Recordset));
		m_Connection.CreateInstance(__uuidof(Connection));	
	}
	catch(_com_error &e)
	{
		printf("Description = %s\n", (char*) e.Description());   
	}
	catch(...)
	{
	}
}

CRADatabase::~CRADatabase()
{
	// Clean up ADO objects

	try
	{
		if (m_Connection)
		{
			if(m_Connection->State == adStateOpen)
			{
				m_Connection->Close();
				m_Connection.Release();			
			}
		}
		if (m_Recordset)
		{
			if(m_Recordset->State == adStateOpen)
			{
				m_Recordset->Close();
				m_Recordset.Release();			
			}
		}		

		m_Connection = NULL;
		m_Command = NULL;
		m_Recordset = NULL;

		CoUninitialize();
	}
	catch(_com_error &e)
	{
		printf("Description = %s\n", (char*) e.Description());   
	}
	catch(...)
	{
	}
}

HRESULT CRADatabase::RAConnect(const char *ConnectionString)
{
	// Attemp a connect, reconnect, or leave if already connected

	if (strlen(ConnectionString) > 0)
	{
		try
		{
			if (m_Connection == NULL)
				m_Connection.CreateInstance(__uuidof(Connection));
			if (0 == _stricmp(ConnectionString, m_ConnectionString) && 
				m_Connection->State == adStateOpen)
				return S_OK;
			else
			{
				if (m_Connection->State == adStateOpen)
					m_Connection->Close();
				sprintf(m_ConnectionString, ConnectionString);
			}
			// Perform the connect

			if (S_OK == m_Connection->Open((char*)m_ConnectionString, 
				L"", 
				L"", 
				adModeUnknown))
				return S_OK;
		}
		catch(_com_error &e)
		{
			printf("Description = %s\n", (char*) e.Description());   
		}
		catch(...)
		{
		}
	}
	return E_FAIL;
}

_RecordsetPtr CRADatabase::RAGetDisconnectedRs(const char *SqlStatement)
{
	// Attempt get a disconnected RS and terminate the connection to the DB

	if (strlen(SqlStatement) > 0)
	{		
		try
		{
			if (m_Connection == NULL || m_Connection->State == adStateClosed)
				RAConnect(m_ConnectionString);

			if (m_Recordset)
			{
				if (m_Recordset->State == adStateOpen)
					m_Recordset->Close();
			}
			else
			{				
				m_Recordset.CreateInstance(__uuidof(Recordset));
			}

			m_Recordset->CursorLocation = adUseClient;
			
			m_Recordset->Open(SqlStatement,
				m_Connection.GetInterfacePtr(),
				adOpenForwardOnly, 
				adLockBatchOptimistic, 
				-1);

			m_Recordset->PutRefActiveConnection(NULL); 
			
			if(m_Connection->GetState() == adStateOpen)
				m_Connection->Close();
			//m_Connection.Release();

			//m_Connection = NULL;		

						
			return m_Recordset.Detach();			
		}
		catch(_com_error &e)
		{
			printf("Description = %s\n", (char*) e.Description());   
		}
		catch(...)
		{
		}
	}
	return NULL;
}


HRESULT CRADatabase::RAExecuteNoRs(const char *SqlStatement)
{
	// Attempt to execute a SQL statement and leave connection open

	if (strlen(SqlStatement) > 0)
	{		
		try
		{
			if (m_Connection == NULL || m_Connection->State == adStateClosed)
				RAConnect(m_ConnectionString);

			m_Connection->Execute(SqlStatement, NULL, adExecuteNoRecords );
			
			return S_OK;
		}
		catch(_com_error &e)
		{
			printf("Description = %s\n", (char*) e.Description());   
		}
		catch(...)
		{
		}
	}
	return E_FAIL;
}

_RecordsetPtr CRADatabase::RAExecuteRs(const char *SqlStatement)
{
	// Attempt to execute a SQL statement, return the RS, and leave connection open

	if (strlen(SqlStatement) > 0)
	{		
		try
		{
			if (m_Connection == NULL || m_Connection->State == adStateClosed)
				RAConnect(m_ConnectionString);
			if (m_Recordset)
			{
				if (m_Recordset->State == adStateOpen)
					m_Recordset->Close();
			}
			else
			{				
				m_Recordset.CreateInstance(__uuidof(Recordset));
			}
			
			m_Command->ActiveConnection = m_Connection;
			m_Command->CommandType = adCmdText;
			m_Command->CommandText = SqlStatement;
			
			_variant_t vNull;
			vNull.vt = VT_ERROR;
			vNull.scode = DISP_E_PARAMNOTFOUND;
			
			m_Recordset = m_Command->Execute( &vNull, &vNull, adCmdText );
		
			
			return m_Recordset.Detach();
		}
		catch(_com_error &e)
		{
			printf("Description = %s\n", (char*) e.Description());   
		}
		catch(...)
		{
		}
	}

	return NULL;
}