DATAWAREHOUSING.md

It is rare that your applications database will have all the data you need and be structured in a way that lets you ask all of the questions you are interested in. Typically an application database will have a schema optimized for small reads and updates, while most analytics queries typically touch a large fraction of a table.

Ingestion

From other databases

If you database is small enough, then it is generally easy enough to dump the whole database and then ingest it into your datawarehouse.

Postgres

MySQL

Heroku

Events

Third party data

Transformation

Uniques

Event Enrichment

Denormalization

Working backwards from Metrics Example