/spanner-basics

Client Library Usage

Instructions on how to install the Google Cloud SDK can be found at Install the Google Cloud SDK.

Client Libraries

Google Cloud client libraries provide an idiomatic way to interact with Spanner from your preferred programming language.

Python

• Installation:

  pip install google-cloud-spanner

• Usage Example:

  from google.cloud import spanner
  
  spanner_client = spanner.Client()
  instance = spanner_client.instance("my-instance-id")
  database = instance.database("my-database-id")
  with database.snapshot() as snapshot:
      results = snapshot.execute_sql("SELECT 1")
      for row in results:
          print(row)

• Python Reference

Java

• Maven Dependency:

  <dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>google-cloud-spanner</artifactId>
  </dependency>

• Usage Example:

  SpannerOptions options = SpannerOptions.newBuilder().build();
  Spanner spanner = options.getService();
  DatabaseClient dbClient = spanner.getDatabaseClient(DatabaseId.of(options.getProjectId(), "my-instance-id", "my-database-id"));
  ResultSet resultSet = dbClient.singleUse().executeQuery(Statement.of("SELECT 1"));
  while (resultSet.next()) {
      System.out.println(resultSet.getLong(0));
  }

• Java Reference

Node.js

• Installation:

  npm install @google-cloud/spanner

• Usage Example:

  const {Spanner} = require("@google-cloud/spanner");
  
  const spanner = new Spanner({projectId: "my-project-id"});
  const instance = spanner.instance("my-instance-id");
  const database = instance.database("my-database-id");
  const [rows] = await database.run({sql: "SELECT 1"});

• Node.js Reference

Go

• Installation:

  go get cloud.google.com/go/spanner

• Usage Example:

  ctx := context.Background()
  client, err := spanner.NewClient(ctx, "projects/my-project-id/instances/my-instance-id/databases/my-database-id")
  if err != nil {
      log.Fatalf("Failed to create client: %v", err)
  }
  defer client.Close()
  iter := client.Single().Query(ctx, spanner.Statement{SQL: "SELECT 1"})
  defer iter.Stop()

• Go Reference

Additional Libraries

LangChain Integration

Spanner integrates with LangChain to help you build LLM-powered applications.

• Vector Store: Use SpannerVectorStore to store and search vector embeddings.
• Document Loader: Use SpannerLoader to load data from Spanner.
• Chat Message History: Use SpannerChatMessageHistory to store conversation history.

For more information, see the Spanner guide for LangChain.

Spring Data Spanner

For Java applications using the Spring Framework, the Spring Data Spanner module provides a familiar Spring Data interface.

For more information, see Add Spring Data Spanner to your application.