Why a Data Warehouse is separated from Operational Databases?

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A data warehouse is kept separate from operational databases due to the following reasons:

  • Data Warehouse queries are complex because they involve the computation of large groups of data at summarized levels.
  • It may require the use of distinctive data organization, access, and implementation method based on multidimensional views.
  • Performing OLAP queries in an operational database degrade the performance of functional tasks.
  • Data Warehouse is used for analysis and decision making in which extensive database is required, including historical data, which operational database does not typically maintain.
  • The separation of an operational database from data warehouses is based on the different structures and uses of data in these systems.
  • Because the two systems provide different functionalities and require different kinds of data, it is necessary to maintain separate databases.

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