What are the functions of Data Warehousing.

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 Functions of Data Warehousing

  • Data Extraction: Involves gathering data from multiple heterogeneous sources.
  • Data Cleaning: Involves finding and correcting the errors in data.
  • Data Transformation: Involves converting the data from legacy format to warehouse format.
  • Data Loading: Involves sorting, summarizing, consolidating, checking integrity, and building indices and partitions.
  •  Refreshing: Involves updating from data sources to the warehouse.

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