Download Apache Druid JDBC Driver

Download the Apache Druid JDBC driver, copy the JDBC URL into DbSchema, and start designing schemas with ER diagrams — free Community Edition.

About the Apache Druid JDBC driver

A JDBC driver is a Java .jar library that lets applications connect to Apache Druid. DbSchema uses JDBC to reverse engineer schemas, run SQL, and generate documentation. Driver files are usually published by the database vendor or an open-source project.

JDBC URL format

Host, port, database name, and SSL options are passed in a URL starting with jdbc:. Each Apache Druid driver uses its own syntax — see the connection details below.

The Apache Druid JDBC driver

Apache Druid is a high-performance, real-time analytics database designed for large-scale event-driven data and sub-second OLAP queries. It ingests streaming and batch data, stores it in columnar segments, and serves fast aggregations at scale. Druid is widely used for operational analytics, dashboards, and applications requiring real-time query performance.

The Apache Druid JDBC URL

• Required File(s): avatica-xxx.jar
• Java Driver Class: org.apache.calcite.avatica.remote.Driver
• JDBC URL: jdbc:avatica:remote:url=http://{HOST}:{PORT}/druid/v2/sql/avatica/
• Website: Apache Druid

Connect to the Druid Broker node on port 8082. The Avatica driver is included with the Druid distribution or available separately from Apache Calcite. No additional authentication configuration is required for basic setups, though TLS and Kerberos can be enabled for secured clusters.

Connecting to Apache Druid

Druid speaks JDBC through Avatica, so the URL wraps an HTTP endpoint rather than naming a host and port directly. Which Druid process that endpoint belongs to matters more than it looks.

1. Point the endpoint at a Broker. The URL is jdbc:avatica:remote:url=http://BROKER:8082/druid/v2/sql/avatica/, with 8082 the Broker's port. Note the trailing slash — Avatica is particular about the path.
2. Connect to one Broker, or go through the Router. Druid's JDBC server does not share connection state between Brokers, so an ordinary load balancer in front of several of them breaks sessions unpredictably. Either name a single Broker, or use the Router, which provides the sticky routing JDBC needs.
3. Expect a flat schema. Druid datasources appear as tables without foreign keys, so the diagram shows structure and column types rather than relationships.
4. Open port 8082 in the server's firewall. The database listens on port 8082 unless it was installed with a different one. A host firewall on the server blocks incoming connections on that port until a rule allows them. The firewall guide has the commands for Windows, ufw, firewalld and iptables.
5. Connect from DbSchema. In the Connection Dialog choose Remote computer or custom port, fill in the server host and the port, then press Test Connection to check that the server answers before you connect.

DbSchema and Apache Druid

DbSchema uses the Avatica JDBC driver to connect to Apache Druid's SQL interface, rendering datasource schemas and enabling interactive SQL editing against Druid's real-time OLAP engine. Use the data explorer to browse ingested segments and their column distributions.