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About QuestDB
QuestDB is a high-performance, open-source time-series database built from the ground up in Java, C++, and Rust with zero dependencies and zero garbage collection. It implements ANSI SQL with native time-series extensions like SAMPLE BY and LATEST ON, supports PostgreSQL wire protocol for compatibility, and offers blazingly fast ingestion with sub-millisecond query latencies. QuestDB excels in financial markets, IoT, and real-time analytics scenarios where ultra-high performance is critical.
GreptimeDB vs. QuestDB
| Feature/Aspect | GreptimeDB | QuestDB |
|---|---|---|
| Data Model | Unified Observability Database | High-Performance Time-Series Database |
| Value Model | Multi-Value (supports complex data structures) | Multi-Value (columns with various data types) |
| Multi-model Support | Metrics, Logs & Traces in one database | Time-series data only |
| Query Languages | SQL & PromQL (dual interface) | SQL with time-series extensions (SAMPLE BY, LATEST ON) |
| Ingestion Protocols | SQL gRPC InfluxDB Line Protocol Prometheus Remote Storage OpenTelemetry Loki Push API Elasticsearch Bulk API HTTP API | InfluxDB Line Protocol PostgreSQL wire REST API CSV upload |
| Storage Format | Apache Parquet (columnar, compressed) | Custom columnar format with native compression |
| Data Retention | Flexible TTL policies with tiered storage | Partitioning and data lifecycle management |
| Continuous Aggregation | Built-in SQL aggregation, Pipeline ETL engine & Flow streaming computation | SQL aggregation functions with SAMPLE BY |
| Use Cases | Unified observability, real-time analytics, IoT monitoring, edge computing | Financial tick data, IoT sensors, real-time dashboards, trading systems |
| Architecture | Cloud-native distributed with compute-storage separation | Single-node optimized with memory-mapped files |
| Deployment Options | Single-node, cluster, Kubernetes-native, edge-to-cloud with unified API | Primarily single-node with enterprise clustering |
| Storage Scalability | Object storage integration with unlimited capacity | Vertical scaling with memory-mapped file optimization |
| High Availability | Native clustering with automatic failover | Enterprise features for clustering and replication |
| License | Apache 2.0 | Apache 2.0 |
| Operational Complexity | Single unified system with simplified Kubernetes operations | Simple single-node deployment, complex for clustering |
| Written Language | Rust (memory safety, performance) | Java, C++, Rust (performance hybrid) |
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