Oracle Objects for OLE (OO4O) Oracle Objects for OLE (OO4O) is a COM-based data access driver that combines seamless and optimized access to Oracle databases with easy to use interfaces. OO4O can be used in a variety of environments ranging from web applications to n-tier client/server applications. It can be used from virtually any programming or scripting language that supports the Microsoft COM Automation technology, such as Visual Basic, Visual C++, VBA in Excel, Active Server Pages, PowerBuilder, Delphi, Microsoft Internet Information Services, and Microsoft Distributed Transaction Coordinator.Because it is a native driver, OO4O generally provides the fastest performance on Windows clients to Oracle databases. It does not incur the overhead of ODBC and OLE DB drivers. OO4O has been developed and has evolved specifically for use with Oracle database servers. It provides easy access to features that are unique to Oracle, but are otherwise cumbersome or inaccessible to use from ODBC and OLE DB-based components, such as ADO.