Data warehouse: DWS layer design principle

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brief introduction

For the stratification of data warehouse , I think everyone is familiar with . be based on OneData Three levels of data warehouse division of methodology ： Data import layer （ODS,Operational Data Store）、 Data common layer （CDM,Common Dimenions Model） And data application layer （ADS,Application Data Store） It's been in people's hearts for a long time .

Of course! , It involves how to develop each layer 、 modeling , Maybe everyone has their own understanding .

But fortunately, everyone's understanding of the importance of data modeling is consistent , If we compare the index to the fruit on the tree , So the model is like the trunk of a tree , To make the fruit bear well , We have to make the trunk strong .

Let's think about it first , What is the original intention of building a data platform ：

• Missing reusable data
• You have to use raw data for cleaning 、 Process and calculate indicators
• The development of a lot of repetitive code consumes resources

The root of the problem is that the data model cannot be reused , And data development are chimney . So to solve this problem , We need to figure out how to design a robust data model .

Layered design idea of data warehouse

The following figure is the logical architecture of data warehouse hierarchy , Big