Windows Data Access Components SDK Overview

Windows Data Access Components (Windows DAC) 6.0 is a set of technologies included in Windows Vista to provide access to information across the enterprise. These technologies include Microsoft ActiveX Data Objects (ADO), OLE DB, and Microsoft Open Database Connectivity (ODBC). Data-driven client/server applications deployed over the Web or a LAN can use these components to easily integrate information from a variety of sources, both relational (SQL) and non-relational.

A Note Regarding Data Access Components Versioning

The same set of data access technologies—ADO, OLE DB, and ODBC—was included with Windows XP Service Pack (SP) 2 and Windows Server 2003, under the name of Microsoft Data Access Components (MDAC) 2.8. Windows XP and Windows Server 2003 continue to use MDAC 2.8.

A redistributable version, MDAC 2.8 SP1, is also available. Note that this version should only be installed on Windows 2000. For more information, see Redistributing MDAC 2.8 SP1.

This documentation includes information about various versions of the data access components. Where no version is specified, the content applies to both Windows DAC 6.0 and MDAC 2.8.

Open Database Connectivity (ODBC)

The Microsoft Open Database Connectivity (ODBC) interface makes it possible for applications to access data from a variety of DBMSs. ODBC permits maximum interoperability — an application can access data in diverse DBMSs through a single interface. Furthermore, that application will be independent of any DBMS from which it accesses data. Users of the application can add software components called drivers, which create an interface between an application and a specific DBMS.

For more information, see Microsoft Open Database Connectivity (ODBC). This section documents the ODBC interface, including a Programmer's Reference, documentation for various ODBC drivers, and samples.


Microsoft OLE DB is a set of interfaces that expose data from a variety of relational and nonrelational sources by using the Component Object Model (COM). OLE DB interfaces provide applications with uniform access to data stored in diverse information sources. These interfaces support the amount of DBMS functionality appropriate to the data store, enabling the data store to share its data.

OLE DB comprises a programmatic model consisting of data providers, which contain and expose data; data consumers, which use data; and service components, which process and transport data (such as query processors and cursor engines). In addition, OLE DB includes a bridge to ODBC to enable continued support for the broad range of ODBC relational database drivers.

For more information, see Microsoft OLE DB. This section documents the OLE DB and OLE DB for OLAP interfaces, including a Programmer's Reference, documentation for various OLE DB providers, and samples.

ActiveX Data Objects (ADO)

ActiveX Data Objects (ADO) provides consistent, high-performance access to data and supports a variety of development needs, including the creation of front-end database clients and middle-tier business objects that use applications, tools, languages, or Internet browsers. The primary benefits of ADO are ease of use, high speed, low memory overhead, and a small disk footprint.

ADO provides an easy-to-use interface to OLE DB, which provides the underlying access to data. It uses a familiar metaphor — the COM Automation interface — available from all leading Rapid Application Development (RAD) tools, database tools, and languages.

For more information, see Microsoft ActiveX Data Objects (ADO). This section contains documentation for ADO, ADOX, ADO MD, and RDS, including samples documentation.

See Also


Redistributing MDAC 2.8 SP1