OLAP
Summary: Online Analytic Processing (OLAP) refers to database access patterns where queries scan huge numbers of records to calculate aggregate statistics for business intelligence.
Sources: chapter3
Last updated: 2026-04-15
Characteristics
OLAP systems are primarily used by internal analysts for decision support. Key characteristics include:
- Read Pattern: Aggregates over a large number of records (source: chapter3).
- Write Pattern: Bulk imports (ETL) or event streams (source: chapter3).
- Dataset Size: Terabytes to petabytes (source: chapter3).
- Constraint: Disk bandwidth is often the primary bottleneck (source: chapter3).
Optimization
Because OLAP queries often only need a few columns from a very wide table, they frequently employ column-oriented-storage (source: chapter3). They may also use materialized-views or data cubes to cache common aggregates (source: chapter3).