OLE DB로 oracle이건 MSSQL이건 데이터를 가져오기 위한 기초 코드

private OleDbDataReader rd;
private OleDbConnection Conn;
private string strRet;
private OleDbCommand cmd;
private StringBuilder sbSQL;
private OleDbParameter paramnSeq;

try
{
	// SQLOLEDB MSDAORA
	Conn = new OleDbConnection("Provider=MSDAORA;Data Source=(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.xxx )(PORT = 1521)))(CONNECT_DATA = (SERVER = DEDICATED)(SERVICE_NAME = GROUP))); User Id =; Password =;");
	Conn.Open();

	try
	{
		sbSQL = new StringBuilder();

		sbSQL.Append(" SELECT * ");
		sbSQL.Append(" FROM HEIS_CUSTOMER ");
		sbSQL.Append(" WHERE 1=1 ");
		sbSQL.Append(" AND CUSTOMER_CODE = ? ");

		paramnSeq = new OleDbParameter("CUSTOMER_CODE", OleDbType.Char, 4);
		paramnSeq.Value = "0003";

		cmd = new OleDbCommand(sbSQL.ToString(), Conn);
		cmd.Parameters.Add(paramnSeq);

		rd = cmd.ExecuteReader();

		if (rd.Read())
		{
			strRet = rd["CUSTOMER_CODE"].ToString();
		}
		else
		{
			strRet = "";
		}
	}
	catch (System.Exception e1)
	{
		throw e1;
	}
	finally
	{
		rd.Close();
	}
}
catch (System.Exception e2)
{
	throw e2;
}
finally
{
	Conn.Close();
}