Time-Series Database overview

Database purpose-built for storing and querying time-stamped, append-heavy data streams such as metrics, sensor readings, events, and financial tick data. TSDBs exploit temporal locality and columnar compression to store high-cardinality time series efficiently. Prometheus stores metrics scraped from service endpoints and is the standard Kubernetes monitoring TSDB. InfluxDB (with Flux/InfluxQL) and TimescaleDB (a PostgreSQL extension) target higher ingest rates and longer retention. VictoriaMetrics is a high-performance Prometheus- compatible alternative. Key concerns include retention policies, downsampling, cardinality management, and PromQL/Flux query optimization.