OLAP (Online Analytical Processing)

OLAP — online analytical processing — is the workload of analysis: queries that scan and aggregate millions of rows to answer questions like revenue by region by quarter. Few queries, each large; overwhelmingly reads; latency measured in seconds rather than milliseconds.

OLAP systems — warehouses, columnar engines, lakehouse query engines — optimize for this shape with columnar storage, compression, and denormalized models like the star schema. The contrast with OLTP (many small transactional operations) is the founding distinction of data architecture: one shape runs the business, the other understands it, and each needs storage designed for its own access pattern.

Go deeper: OLTP vs OLAP: Why You Shouldn't Run Analytics on Your App Database