You have to know basics of database management first.

Then I recommend to read Ralph Kimball's series of books on Data Warehousing (Kimball Architecture pattern).

The other pattern is Innoman architecture. There's a book by Innoman.

You should learn about OLAP basics, data cubes, ETL, ELT, columnar databases, data lake etc. for further knowledge.

Evan Gertis ,

Before learning about data warehousing I would suggest a thorough introduction to databases such as Ullman[1]. Without knowing the computational costs of query compiler, record manager storage manager, the normal forms impact and the join process complexity you will not understand the design of the star schema (snowflake and constellation) and its underlying benefits.

The first thing I would ask is as to the rational for using a transactional database in the first place so that you need a data warehouse ( I manage terabytes of data without such structures and have extraction times faster than with those structures). As with all technologies as tools, each has its own place and right use.

Questions to ask when using a transactional DB and data warehouse:

• If you do not have transactional data with high update times, I would not even bother with a transactional DB to begin with much less a DW (other factors include record level queries, multi relational data, etc.)
• If you have less than 35% usage on the primary DB It is not worth the trouble to use a DW, much less invest on separating them on multiple servers

If an application meets the requirements then moving the data from the DB to the DW requires ETL's as Thamalu Maliththa Piyadigama mentioned. you should also learn OLAP as he said on the previous post.

DW's are not the only answer to efficient extraction and other technologies such as key-value store, document store, column and graph dbs are also important and each have their place.

[1] Garcia-Molina, H. (2008). Database systems: the complete book. Pearson Education India.

Dear Evan Gertis

I recommend the following 7 Data Warehousing Steps:

Step 1: Establish Business Goals.

Step 2: Collect and analyze data in step two.

Step 3: Determine the Core Business Processes.

Step 4: Build a Conceptual Data Model.

Step 5: Identifying Data Sources and Planning Data Transformations

Step 6: Define the Tracking Duration.

Step 7: Put the Plan into Action.

For detailed illustration, have a look: https://www.itprotoday.com/sql-server/7-steps-data-warehousing

Kind Regards

Qamar Ul Islam