InfluxDB
What it is: Purpose-built time-series database. Optimized for metrics, events, IoT sensor data. Handle millions of writes per second.
What It Does Best
High-velocity writes. Columnar storage, aggressive compression. 10x better compression than traditional databases.
Time-based queries. Downsampling, retention policies, continuous queries. Automatically manage data lifecycle.
TICK stack. Telegraf (collection), InfluxDB (storage), Chronograf (viz), Kapacitor (alerting). Complete monitoring platform.
Key Features
Flux query language: Powerful data scripting and transformation
Retention policies: Automatic data expiration and downsampling
Continuous queries: Pre-compute aggregations automatically
Tags and fields: Efficient indexing for time-series data
Native integrations: Telegraf plugins for 200+ data sources
Pricing
Open Source: Free, InfluxDB 2.x (MIT license, self-hosted)
InfluxDB Cloud: $0.002/MB ingested, $0.002/MB queried
Free tier: 30-day retention, limited writes/queries
Usage-based: Pay only for what you use, no minimums
When to Use It
✅ Application performance monitoring (APM)
✅ IoT sensor data and telemetry
✅ DevOps monitoring and metrics
✅ Real-time analytics dashboards
✅ High-frequency measurement data
When NOT to Use It
❌ Relational data or complex joins
❌ Data without timestamps
❌ Long-term data storage (use cold storage + downsampling)
❌ General-purpose database needs
❌ Low write volume (overkill for simple use cases)
Common Use Cases
Server monitoring: CPU, memory, disk metrics from infrastructure
Application metrics: Request rates, latency, error counts
IoT telemetry: Sensor readings from connected devices
Financial data: Stock prices, trading volumes, market data
Network monitoring: Bandwidth, packet loss, latency metrics
InfluxDB vs Alternatives
vs Prometheus: InfluxDB better for long-term storage, Prometheus simpler for metrics
vs TimescaleDB: InfluxDB purpose-built for time-series, TimescaleDB extends PostgreSQL
vs Elasticsearch: InfluxDB more efficient for pure time-series, Elasticsearch better for search
Unique Strengths
Purpose-built: Optimized specifically for time-stamped data
Compression: Exceptional compression ratios for time-series
TICK stack integration: Complete monitoring solution out of box
Flux language: Powerful data transformation and analysis
Bottom line: Default choice for time-series data. Metrics, sensors, events—InfluxDB handles them efficiently. Flux query language takes learning, but worth it. Free tier is generous for small projects.