Securing ClickHouse in Java Applications for Spring Boot

November 20, 2025

This guide shows how to secure ClickHouse connections in Spring Boot applications with authentication, SSL, and restricted access.

1. Enable User Authentication in ClickHouse

Create a dedicated user with limited permissions.

<!-- users.xml -->
<users>
  <app_user>
    <password>strongpassword</password>
    <networks>
      <ip>::/0</ip>
    </networks>
    <profile>default</profile>
    <quota>default</quota>
  </app_user>
</users>

2. Configure Spring Boot with Credentials

spring.datasource.url=jdbc:clickhouse://localhost:8443/default?ssl=true
spring.datasource.username=app_user
spring.datasource.password=strongpassword
spring.datasource.driver-class-name=com.clickhouse.jdbc.ClickHouseDriver

3. Use SSL for Secure Connections

Enable TLS in ClickHouse server and use SSL options in JDBC.

spring.datasource.url=jdbc:clickhouse://localhost:8443/default?ssl=true&sslmode=STRICT

4. Restrict Network Access

Allow only specific IPs in users.xml.

<networks>
  <ip>192.168.1.100</ip>
</networks>

5. Parameterized Queries

Always use prepared statements to avoid SQL injection.

@Query(value = "SELECT * FROM events WHERE type = :type", nativeQuery = true)
List<Event> findByType(@Param("type") String type);

6. Encrypt Sensitive Data

Use Java libraries like JCE or Spring Security Crypto for encrypting fields before inserting into ClickHouse.

7. Monitor Security

Check system.query_log for suspicious queries.
Use quotas and roles to limit query abuse.