Google Cloud Spanner Graph

Protocols gRPC, HTTP/REST

Client libraries and the RPC API run over gRPC; a REST API is also offered with reduced feature support (e.g. no cancellation, no deadlines, partial streaming).

• You can use the Google Cloud console, Google Cloud CLI, client libraries, the REST API, or the RPC API to run a Spanner Graph query.

  Spanner Graph queries overview · reviewed 2026-08-02

• The Spanner client libraries are available in multiple languages and are built on gRPC.

  Overview of APIs, client libraries, and ORM drivers | Spanner | Google Cloud Documentation · reviewed 2026-08-02

License Proprietary

No LICENSE file or source repository exists; a Wikipedia comparison table lists it as Proprietary, but the evidence is a table cell rather than prose. Confirms current value.

• Proprietary C++ A horizontally scalable, multi-model database that provides a native graph experience on top of Spanner

  Graph database - Wikipedia · reviewed 2026-08-02

Released 2024-08

Google's own launch blog post is dated August 1, 2024, matching the current value.

• Today, we are thrilled to announce Spanner Graph, a groundbreaking offering that unites purpose-built graph database capabilities with Spanner, our always-on, globally consistent, and virtually unlimited-scale database.

  Announcing Spanner Graph | Google Cloud Blog · reviewed 2026-08-02

Language C++

No public source tree exists for this managed feature. A Wikipedia comparison table attributes it to C++, consistent with Spanner's underlying C++ implementation, but the evidence is a table cell rather than prose.

• Proprietary C++ A horizontally scalable, multi-model database that provides a native graph experience on top of Spanner

  Graph database - Wikipedia · reviewed 2026-08-02