Data Warehousing

As the amount of data a business collects grows, turning it into usable information gets harder. Not all of it has the same value. Some is queried every day, some is kept only because a regulation or contract requires it, and some can be summarized and discarded.

What does the design have to decide?

A reporting warehouse is organized around the questions people ask. That means choosing the grain of each fact table (one row per invoice line, or one row per account per day), deciding which attributes need history, such as the sales territory a customer belonged to at the time of each sale as well as today, and loading on a schedule that matches how current the reports need to be. Those choices are hard to change once reports depend on them.

Storage cost, retention rules, security, and regulatory requirements then shape where historical data lives. Cloud platforms make capacity and redundancy easier to add, but storage, compute, and data transfer are all billed, and the options differ widely in price and query speed. A database backup retention policy is also not an archive: backups are recovery material, not a business archive that analysts can query directly. We lay out the options with their costs so the choice fits your budget.

Reports built on the warehouse are covered under Reporting.