OLAP
ELI5 — The Vibe Check
OLAP is all about analyzing huge amounts of data to answer business questions. 'What were total sales by region last quarter?' That's an OLAP query. It reads millions of rows, aggregates them, and gives you a summary. The opposite of OLTP, which handles one transaction at a time like a cash register.
Real Talk
Online Analytical Processing (OLAP) describes workloads characterized by complex, read-heavy queries that scan large volumes of data for aggregation, reporting, and trend analysis. OLAP systems use columnar storage, materialized views, and parallel query execution to achieve performance. Examples include data warehouses (BigQuery, Snowflake) and OLAP engines (ClickHouse, Apache Druid).
When You'll Hear This
"OLAP queries scan millions of rows to produce a single dashboard chart." / "Don't run OLAP queries on your OLTP database, it'll crush your app's performance."
Related Terms
Columnar Storage
Columnar storage saves data column by column instead of row by row. All the ages together, all the names together, all the emails together.
Data Warehouse
A data warehouse is where all your company's data goes to be analyzed.
OLTP
OLTP is the workhorse behind every app. It handles fast, small transactions: creating users, placing orders, updating profiles.
Star Schema
A star schema organizes your warehouse like a star.