This is the implementation of the Cloud Spanner data handler for MindsDB. Cloud Spanner is a fully managed, mission-critical, relational database service that offers transactional consistency at global scale, automatic, synchronous replication for high availability. It supports two SQL dialects: GoogleSQL (ANSI 2011 with extensions) and PostgreSQL.

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Implementation

This handler was implemented using the google-cloud-spanner Python client library. The required arguments to establish a connection are as follows:
  • instance_id is the instance identifier.
  • database_id is the database identifier.
  • project is the identifier of the project that owns the resources.
  • credentials is a stringified GCP service account key JSON.
If you installed MindsDB locally via pip, you need to install all handler dependencies manually. To do so, go to the handler’s folder (mindsdb/integrations/handlers/cloud_spanner_handler) and run this command: pip install -r requirements.txt.

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Usage

In order to make use of this handler and connect to the Cloud Spanner database in MindsDB, the following syntax can be used: 
CREATE DATABASE cloud_spanner_datasource
WITH
    engine = 'cloud_spanner',
    parameters = {
      "instance_id": "my-instance",
      "database_id": "example-id",
      "project": "my-project",
      "credentials": "{...}"
    };
You can use this established connection to query your table as follows: 
SELECT *
FROM cloud_spanner_datasource.my_table;
Cloud Spanner supports both PostgreSQL and GoogleSQL dialects. However, not all PostgresSQL features are supported.