OLAP Cube engine from eBay (Apache incubator), combines HBase for low latency and Hive for mid latency
- Fast OLAP Cube on HBase + Hive
- uses HBase Coprocessors
- ANSI SQL
- web UI for managing cubes
- ACLs
- Tableau/Microstrategy integration
- LDAP support
- Kylin Framework - Metadata Engine Query Engine Job Engine Storage Engine REST Server (client requests)
- Extensions - plugins
- ODBC + JDBC drivers
- Ambari + Hue plugins
- Integration - Lifecycle Management Support integrates with Job Scheduler, ETL, Monitoring Systems
Pre-computes data along different dimensions of interest and store resultant values in the cube.
MOLAP is much faster but is inflexible.
Uses star or snow-flake schema to do runtime aggregation.
ROLAP is flexible but much slower.
Kylin pre-builds MOLAP in HBase.
If query can be satisfied with it, then it uses HBase.
Otherwise it uses Hive (ROLAP slow).
Ported from private Knowledge Base pages 2014+