Data warehouse data model refers to using entity , Attributes and their relationships define the operation and logic rules of enterprises , Coding and naming

Business system model Data warehouse model
For operational data For analytical data
Business oriented Orientation is the theme
Transactional , A large number of users DML handle Query analysis of a small number of users with large amount of data
Data processed by business processes Historical data and external data sets
High demand for real-time It has a certain degree of time delay
Online transaction processing (OLTP ) On line analytical processing (OLAP)
Data warehouse model =ods+ Dimension model + Wide table model
Dimension model is to analyze the needs of decision-making model design , Star model and snowflake model belong to dimension model .
The wide table is a combination of different business domains , Data fusion of different dimensions , It is convenient for data mining and analysis , Primary storage , Multiple reads , reduce IO, Trade space for time .
data warehouse (Data Warehouse): It's a topic oriented one (Subject
Oriented), Integrated (Integrated), Relatively stable (Non-Volatile), Reflecting historical changes (Time
Variant) Data collection for , Used to support management decisions (Decision Making Support).

: It's a topic oriented one , Integrated , Variable , Current detail data set , It is used to support the enterprise's , Operational , Requirements for integrated all information ,ods It is generally incremental or full storage of detailed data , Retain original cleaned data

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