Microsoft Data Access Components Wikipedia. Microsoft Data Access Components MDAC also known as Windows DAC is a framework of interrelated Microsoft technologies that allows programmers a uniform and comprehensive way of developing applications that can access almost any data store. Its components include Active. X Data Objects ADO, OLE DB, and Open Database Connectivity ODBC. There have been several deprecated components as well, such as the Microsoft Jet Database Engine, MSDASQL the OLE DB provider for ODBC, and Remote Data Services RDS. Some components have also become obsolete, such as the former Data Access Objects. API and Remote Data Objects. Windows Management Instrumentation WMI consists of a set of extensions to the Windows Driver Model that provides an operating system interface through which. The first version of MDAC was released in August 1. At that time Microsoft stated MDAC was more a concept than a stand alone program and had no widespread distribution method. Later Microsoft released upgrades to MDAC as web based redistributable packages. Eventually, later versions were integrated with Microsoft Windows and Internet Explorer, and in MDAC 2. SP1 they ceased offering MDAC as a redistributable package. Throughout its history, MDAC has been the subject of several security flaws, which led to attacks such as an escalated privileges attack, although the vulnerabilities were generally fixed in later versions and fairly promptly. The current version is 2. Microsoft technologies. MDAC is now known as Windows DAC in Windows Vista. ArchitectureeditThe latest version of MDAC 2. Windows specific except for ODBC which is available on several platforms. MDAC architecture may be viewed as three layers a programming interface layer, consisting of ADO and ADO. NET, a database access layer developed by database vendors such as Oracle and Microsoft OLE DB,. NET managed providers and ODBC drivers, and the database itself. These component layers are all made available to applications through the MDAC API. The Microsoft SQL Server Network Library, a proprietary access method specific to Microsoft SQL Server, is also included in the MDAC. Serial Number Uniblue Driver Scanner 2013 Calendar. Developers of Windows applications are encouraged to use ADO or ADO. I am trying to run openrowset from MS SQL Server on an Oracle server. When i execute the following command select from OPENROWSETOraOLEDB. Oracle,srvuser. NET for data access, the benefit being that users of the application program are not constrained in their choice of database architecture except that it should be supported by MDAC. Naturally, developers still have the choice of writing applications which directly access OLE DB and ODBC. Microsoft SQL Server Network LibraryeditThe Microsoft SQL Server Network Library also known as Net Lib is used by the Microsoft SQL Server to read and write data using many different network protocols. Though Net Lib is specific to the SQL Server, Microsoft includes it with MDAC. The SQL Server uses the Open Data Services ODS library to communicate with Net Lib, which interfaces directly with the Windows NT operating system lines Win. The SQL Server Network Library is controlled through the use of a Client Network Utility, which is bundled with the SQL Server. Each Net Lib supported network protocol has a separate driver not to be confused with a device driver, and has support for a session layer in its protocol stack. There are two general types of Net Lib the primary and the secondary. The primary Net Lib consists of a Super Socket Net Lib and the Shared Memory Net Lib, while there are numerous secondary Net Libs, including TCPIP and named pipes network libraries named pipes are a method of communicating with other processes via a system persistent pipeline that is given an identity. The Microsoft OLE DB Provider for SQL Server SQLOLEDB communicates via primary Net Libs. The Super Socket Net Lib deals with inter computer communications and coordinates the secondary Net Libs though the TCPIP secondary Net Lib is an exception in that it calls on the Windows Socket 2 API directly. The Banyan VINES, Apple. Talk, Server. Net, IPXSPX, Giganet, and RPC Net Libs were dropped from MDAC 2. The Network Library router had the job of managing all these protocols, however now only the named pipes secondary Net Lib is managed by the router. The Super Socket Net Lib also handles data encryption via the use of the Windows SSL API. The Shared Memory Net Lib, on the other hand, manages connections between multiple instances of SQL Server that exist on one computer. It uses a shared memory area to communicate between the processes. This is inherently secure there is no need for data encryption between instances of SQL Server that exist on one computer as the operating system does not allow any other process access to the instances area of shared memory. SSIS-OLE-DB-Destination-6.png' alt='Edit Ole Db Query Command Text Property' title='Edit Ole Db Query Command Text Property' />Net Lib is also able to support the impersonation of a logged in users security context for protocols that support authenticated connections called trusted connections. This allows Net Lib to provide an integrated logon authentication mechanism via the use of Windows Authentication. Windows Authentication is not supported on Windows 9. Windows Me. 1OLE DB also called OLEDB or OLE DB allows MDAC applications access to different types of data stores in a uniform manner. Microsoft has used this technology to separate the application from data can store in the website the data store that it needs to access. This was done because different applications need access to different types and sources of data, and do not necessarily need to know how to access technology specific functionality. The technology is conceptually divided into consumers and providers. The consumers are the applications that need access to the data, and the provider is the software component that exposes an OLE DB interface through the use of the Component Object Model or COM. OLE DB is the database access interface technology used by MDAC. OLE DB providers can be created to access such simple data stores as a text file or spreadsheet, through to such complex databases as Oracle and SQL Server. However, because different data store technology can have different capabilities, OLE DB providers may not implement every possible interface available. The capabilities that are available are implemented through the use of COM objects  an OLE DB provider will map the data store technologys functionality to a particular COM interface. Microsoft calls the availability of an interface to be provider specific as it may not be applicable depending on the database technology involved. Additionally, however, providers may also augment the capabilities of a data store these capabilities are known as services in Microsoft parlance. The Microsoft OLE DB Provider for SQL Server SQLOLEDB is the OLE DB provider that Microsoft provides for the Microsoft SQL Server from version 6. According to Microsoft, SQLOLEDB will be the primary focus of future MDAC feature enhancements and will be available on the 6. Windows operating system. Universal data linkeditUniversal data link files or. A user can use a Data Link Properties dialog box to save connection information in a. Consequently, these files provide a convenient level of indirection. Additionally, the dialog box specifies a number of alternate OLE DB data providers for a variety of target applications. Open Database Connectivity ODBC is a native interface that is accessed through a programming language usually C that can make calls into a native library. In MDAC this interface is defined as a DLL. A separate module or driver is needed for each database that must be accessed. The functions in the ODBC API are implemented by these DBMS specific drivers. The driver that Microsoft provides in MDAC is called the SQL Server ODBC Driver SQLODBC, and as the name implies is designed for Microsofts SQL Server. It supports SQL Server v. ODBC allows programs to use SQL requests that will access databases without having to know the proprietary interfaces to the databases. It handles the SQL request and converts it into a request that the individual database system understands. Active. X Data Objects ADO is a high level programming interface to OLE DB.