What is a data warehouse?
A data warehouse is a database to sort out huge amount of data and to save by purpose.
Data warehouse isn’t only to save data, strong point is to save by purpose by time series.
And Data warehouse is specialized to analyze data.
Data warehouse is recognized as system to contribute to improve efficiency of business and expand profit margin.
What is a data lake
A data lake is place to store distributed data.
Data lake is similar to data warehouse, but It’s difference data content to save.
Data lake can save anything, for example video, audio, text file, etc.
Data warehouse can only save structured data, but Data lake isn’t so.
What is a data mart
A data mart is place to save processed data by purpose.
In data mart, process data of data warehouse.
The purpose to process data is to make easier to analyze data.
Difference of DWH and RDB
DWH and RDB are a system to save data.
Doesn’t change much.
But there is difference a little bit.
RDB is to save a raw data of system.
DWH is to save a processed data to analyze.
In RDB save the raw data, In DWH process data of RDB’s.
