Additional EII Services for Data Warehousing - dummies

Additional EII Services for Data Warehousing

By Thomas C. Hammergren

Your virtual data warehousing environment includes services that a single database would handle in a centralized environment. These true middleware services complement the traditional data warehousing middleware, such as extraction and transformation:

  • A unified metadata service: Users see a single logical view of the environment’s contents without having to know the location and particulars of each component.

  • A directory service: Individual components within the environment, even if they’re relocated or otherwise modified.

  • Security services: These services handle permissions, authentication, and other security needs in a distributed environment.

  • Synthesis services: Unlike traditional Internet usage, for example, where each hit returns information that probably won’t have to be correlated with information from other hits, a virtual data warehouse might have to combine facts from one component with facts from another.

    This figure shows a synthesis service component within the virtual data warehouse.


    If the data warehousing environment, which “knows” that it’s virtually (remotely) accessing data from multiple sources, has a component that handles the synthesis of results from the other components, the responsibility for consolidating these independent results sets can be offloaded from the requesting business intelligence tool.

  • Transaction-management services: In addition to the synthesis service, which is a type of transaction-management function, these services provide routing, load balancing, conflict resolution, and other functions necessary to ensure data integrity. (Yes, you need these services, even in a supposedly read-only environment.)