CHAPTER 8 - ACCESSING ORGANIZATIONAL INFORMATION - DATA WAREHOUSE

• Data warehouse - a logical collection of information - gathered from many different operational databases - that supports business analysis activities and decision-making tasks.
• The primary purpose of a data warehouse is to combined information throughout an organization into a single repository for decision making purposes - data warehouse support only analytical processing.
• Extraction, transformation, and loading (ETL) - a process that extracts information from internal and external databases, transforms the information using a common set of enterprise definitions, and loads the information into a data warehouse.
• Data warehouse then send subsets of the information to data mart
• Data mart - contains a subset of data warehouse information.

• In a data warehouse and data mart, information is multidimensional, it contains layers of columns and rows.
• Cube - common term for the representation of multidimensional information.

• Data mining - the process of analyzing data to extract information not offered by the raw data alone.
• To perform data mining users need data-mining tools.
• Information cleansing or scrubbing - a process that weeds out and fixes or discards inconsistent or incorrect, or incomplete information. 
• Occur during ETL process and second on the information once it is in the data warehouse.
  
  
  

• Business Intelligence - refers to applications and technologies that are used to gather, provide access, analyze data, and information to support decision making effort.