Google Cloud Spanner vs VoltDB

Google Cloud Spanner is a paid database service combining relational, graph, key-value, and search capabilities. It provides Strong-ACID transactions ordered with TrueTime, horizontal read and write scaling, automatic sharding, and geo-partitioning. Configurations include single-region, dual-region, and multi-region deployments, with Google describing availability up to 99.999%. Spanner Graph, vector search, and built-in full-text search are included. A columnar engine supports ad hoc analytics on live data, and BigQuery integration enables federated queries. Spanner Omni is downloadable for on-premises, cross-cloud, or laptop deployment. Client libraries cover C++, C#, Go, Java, Node.js, PHP, Python, and Ruby. Integrations include Cloud Run, Dataflow, Cloud Storage, Compute Engine, GKE, Gemini Enterprise Agent Platform, and Looker. Security includes encryption in transit and identity and access controls. PostgreSQL compatibility, horizontal scaling, multi-region deployment, geo-partitioning, and HTAP workloads are listed.

VoltDB is a distributed, in-memory database and real-time decisioning layer for data processing, stream ingestion, business logic, and AI integration. Its database partitions data and stored procedures so queries can run in parallel while maintaining ACID consistency. Volt Active Data says Volt is built to move from ingest to action in under 10 milliseconds. Clusters scale by adding nodes, with partitioning automated from the schema. Volt connects directly to Kafka or CDC streams and can expose decisions through SQL, REST, or Kafka topics. It supports on-premises, cloud Kubernetes or VM-based, and hybrid deployments. Production databases support Debian 12.11 or later, RHEL 8.8 or later, Rocky Linux 8.8 or later, and Ubuntu 20.04, 22.04, or 24.04; macOS 13 or later is supported for development. Enterprise Edition provides command logging, locally replicated partitions, and wide-area database replication. Authentication, role-based authorization, and TLS/SSL or Kerberos communications are available, but security is disabled by default. The free Developer Edition is not intended for production workloads. A free 30-day trial is listed for Confluent users; production pricing is on request.