OLAP Online Analytical Processing
Databases optimised for large analytical queries — "crunch all data from the last 5 years".
Column-oriented storage. Snowflake, BigQuery, ClickHouse, Redshift, DuckDB. Different from OLTP (transactional). Modern data stack: OLTP (Postgres) for the app + OLAP (Snowflake) for analytics, ETL between them.