A data warehouse

Have you ever heard the phrase, “A Data Warehouse (DW), Business Intelligence (BI) & Artificial Intelligence (AI) are keys for future business growth”?

But what exactly is a “DW”?
There are many definitions on DW, but one of them is to "collect & store all historical data in the company in one place (ex. Data Base)".

How come it is necessary?

One of the main reasons of implementing a DW is for “Data Analysis (BI)”.
Then, next question is “What is a BI?”. BI is to “change raw data into something meaningful for end-users to make decisions”.
Each company has its own data system, which might be a one-stop data system like ERP, or might be separated by department (Accounting Software, CRM Software, Sales Software, etc).
Also, the format of the data might be different, such as DB, Excel, Word, CSV, etc.
It would be time-consuming & cause many errors/troubles if we need to access each data source above for BI.
This is why we need a DW. With DW, you don’t need to go grab data from each data source but just access the DW where all necessary data are stored. In one word, a DW is a “One-Stop” point for Data Analysis (BI).