Four views regarding the design of a data warehouse and they are top-down view allows selection of the relevant information necessary for the data warehouse, data source view exposes the information being captured, stored, and managed by operational systems, data warehouse view take care of consists of fact tables and dimension tables
, business query view sees the perspectives of data in the warehouse from the view of end-user.
of profit statement (including index code, index name, etc.
are attributes of the fact tables.
The time dimension table
occupies a special place in every data warehouse because almost every fact table is time dependent.
Data are collected directly to OLAP dimension tables
Fact tables, dimension tables
and even the occasional evil bridge table must all be maintained.
Unlike fact tables, dimension tables
are usually wide (have many columns) but don't have many rows.
This is especially suited for enterprises with customer or product dimension tables
that contain millions of rows of data.
The data warehouse included two fact tables (daily forecasts and daily sales) and five dimension tables
(customer, period, product, promotion and store).