Explain the distributed and virtual data warehouse.

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 Distributed Data warehouse:

Most organizations build and maintain a single centralized data warehouse environment. This setup makes sense for many reasons:

  •  The data in the warehouse is integrated across the corporation, and an integrated view is used only at headquarters.
  •  The corporation operates on a centralized business model.
  •  The volume of data in the data warehouse is such that a single centralized repository of data makes sense.
  •  Even if data could be integrated, if it were dispersed across multiple local sites, it would be cumbersome to access.

In short, politics, economics, and technology greatly favor a single centralized data warehouse. Still, in a few cases, a distributed data warehouse makes sense.


Virtual Data warehouse

A virtual warehouse is another term for a data warehouse. A data warehouse is a computing tool designed to simplify decision-making in business management. It collects and displays business data relating to a specific moment in time, creating a snapshot of the condition of the business at that moment. Virtual warehouses often collect data from a wide variety of sources.

A virtual warehouse is essentially a business database. The data found in a virtual warehouse is usually copied from multiple sources throughout a production system. This is done so related data can be searched quickly and without accessing the entire system. Performing a search of an entire production system at one time could potentially compromise the system's performance. Using a data warehouse removes this operating risk and speeds up the overall access process.



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