Learn AI · Level 2 · How AI works · step 6 of 19 · word 3 of 4
What is a data warehouse?
A data warehouse is a central store of cleaned, organised business data, arranged in tables and built for reports, dashboards and analysis.
In plain English
Think of a well-run library. Every book has been checked, labelled and shelved in its place, so finding an answer is quick. A data warehouse does the same for a company’s data: sales, customers and stock, cleaned by ETL and kept in tidy tables that anyone can query. Snowflake, Google BigQuery and Amazon Redshift are well-known examples.
An example
A finance team asks, “What were our sales by country last quarter?” The warehouse answers in seconds, because the data was already cleaned and organised when it arrived.
Watch out
Tidiness has a cost. A warehouse only holds data someone decided to clean and structure in advance, so photos, emails and raw logs usually live in a data lake instead.