Apache IoTDB vs QuestDB

Apache IoTDB is an open-source industrial IoT time-series database for collecting, storing, managing, and analyzing device data across edge and cloud deployments. The project describes high-speed writes for millions of networked devices alongside fast reads. Query features include aligning time across devices and sensors, time-series computation, and aggregation by time dimensions. Ingestion options include IoTDB-SQL, JDBC, Java, C++, Python, and Go native APIs, REST, MQTT, CSV, and TsFile. Named analysis ecosystem examples include Hadoop, Spark, Flink, and Grafana. Deployment options include cloud installation, a desktop terminal tool, and synchronization between cloud and on-premise machines. The REST service is disabled by default and uses Basic Authentication except for the health check endpoint. Data and cluster permissions can be managed through users, roles, and privileges. The homepage states disk storage can cost less than $0.23 per GB. The project lists energy, aerospace, transportation, steel, and other IoT scenarios. Its JDBC documentation cautions that insert operations may not provide high-performance writing and recommends the Java Native API for Java applications.

QuestDB is a time-series database for environments where low latency matters, including mission-critical workloads. It supports standard SQL through a vectorized execution engine, along with time-series extensions such as SAMPLE BY, ASOF, and HORIZON JOIN. QuestDB advertises ingestion speeds of 8M+ rows per second. The Open Source edition is self-managed and available as binaries, containers, or source code; it is single-instance and supports Parquet storage and PostgreSQL Wire Protocol compatibility. Ingestion options include QuestDB Wire Protocol, InfluxDB Line Protocol, REST API, native client libraries, SQL INSERT, Kafka connector, and CSV import. Listed integrations include Grafana, Power BI, Apache Kafka, Telegraf, Redpanda, Apache Flink, Pandas, and Apache Spark. Open Source costs nothing and includes community support. Enterprise adds security controls, replication, automatic failover, object-storage tables, and dedicated support with response-time SLAs.