What is a data warehouse and why is it important to have another version of the data in a data warehouse?
A data warehouse is a type of database which is designed for long term, largely static use. They are used for analysis of trends or referencing specific pieces of data from a long time ago. This is important for having an accurate record of transactions or being able to make decisions based on historical trends. It is important to have these warehouses separate because the main database will become bloated and harder to maintain and query, and it allows for the two databases to be optimized differently for their different uses.