The Role of ADO in Universal Data Access

Universal Data Access is Microsoft's strategy for providing access to information across the enterprise. The basic idea behind UDA is to enable you to efficiently access any data from where it is normally found, rather than moving the data to large, centralized data stores.

UDA is independent of data stores, tools, and languages. It provides a high-level, easy-to-use interface, and a low-level, high-performance interface to practically any data store available. You can use this flexibility to integrate diverse data stores and use your choice of tools, applications, and platform services to create the right solutions for your needs.

The Microsoft Data Access Components (MDAC) comprise the technologies that make UDA work. These technologies provide the basic framework for general-purpose data access in Microsoft® Windows® operating systems.

There are three primary technologies in MDAC. ActiveX Data Objects (ADO) is a high-level, easy-to-use interface to OLE DB. OLE DB is a low-level, high-performance interface to a variety of data stores. ADO and OLE DB both can work with relational (tabular) and nonrelational (hierarchical or stream) data. Finally, Open Database Connectivity (ODBC) is another low-level, high-performance interface that is designed specifically for relational data stores.

ADO provides a layer of abstraction between your client or middle-tier application and the low-level OLE DB interfaces. ADO uses a small set of Automation objects to provide a simple and efficient interface to OLE DB. This interface makes ADO the perfect choice for developers in higher level languages, such as Visual Basic and even VBScript, who want to access data without having to learn the intricacies of COM and OLE DB.