QuestDB
Open-source time-series database for high-speed data ingestion.
QuestDB provides ultra-low latency and high ingestion throughput with support for Parquet and SQL, ensuring data portability.1 save · questdb.com

QuestDB operates as an open-source time-series database, running on a multi-tier storage engine with native support for Parquet and SQL. It is designed for high-speed data ingestion and low-latency queries.
- Column-oriented storage: utilizes a columnar storage model for efficient data retrieval.
- Zero-GC Java core: implemented in Java and C++ for high performance with zero garbage collection.
- Multi-tier architecture: storage engine includes WAL, native, and Parquet tiers.
- SQL extensions: supports time-series specific SQL extensions like ASOF JOIN and SAMPLE BY.
- Open formats: integrates with Parquet and Iceberg for data portability.
Free and open source; Enterprise version available for advanced features. 17.0k GitHub stars; used by tier-1 firms in capital markets.
QuestDB is ideal for developers and data engineers dealing with high-frequency trading and real-time analytics. It suits environments requiring low-latency data processing and high ingestion throughput.