Apache Calcite Avatica: Architecture and Remote Data Access

Overview of Apache Calcite Avatica, describing it as a specialized framework and sub-project of Apache Calcite designed for building remote database drivers using a client-server, RPC-over-HTTP architecture.

Avatica serves as a universal data access gateway, decoupling data consumers from data producers and enabling standardized access to diverse data stores via a thin JDBC driver, which is crucial for polyglot microservices environments.

The communication protocol is flexible, supporting both human-readable JSON for development and the more efficient Protocol Buffers (Protobuf) for performance-critical production use cases. Successful real-world applications include the Phoenix Query Server for Apache HBase and integrations with systems like Apache Druid.

The source also examines performance challenges like latency overhead and discusses the security model, which focuses on authentication while delegating fine-grained authorization to the underlying database.