唐武的博客

摘自： 《Data Mining - Concepts and Techniques》    According toWilliam H. Inmon, a leading architect in the construction of data warehouse systems, “A data warehouse is a subject-oriented, integrated,...

摘自《Data Mining - Concepts and Techniques》 A data cube allows data to be modeled and viewed in multiple dimensions. It is defined by dimensions and facts.

摘自《Data Mining - Concepts and Techniques》     The most popular data model for a data warehouse is a multidimensional model.Such a model can exist in the form of a star schema, a snowflake schema, o...

摘自《Data Mining - Concepts and Techniques》     The most popular data model for a data warehouse is a multidimensional model.Such a model can exist in the form of a star schema, a snowflake schema, o...

摘自《Data Mining - Concepts and Techniques》   Measures can be organized into three categories (i.e., distributive, algebraic, holistic), based on the kind of aggregate functions used. Distributiv...

  Data warehouse systems use back-end tools and utilities to populate and refresh their data (Figure 3.12). These tools and utilities include the following functions: Data extraction,which typical...

摘自《Data Mining - Concepts and Techniques》   Fromthe architecture point of view, there are three data warehouse models: the enterprise warehouse, the data mart, and the virtual warehouse. Enterpri...

摘自《Data Mining - Concepts and Techniques》   In general, the warehouse design process consists of the following steps: 1. Choose a business process to model, for example, orders, invoices, shipmen...

  Four different views regarding the design of a data warehousemust be considered: the top-down view, the data source view, the data warehouse view, and the business query view. The top-down view ...