Google Cloud Spanner

What is Google Cloud Spanner?

Google Cloud Spanner is the world's first fully managed, horizontally scalable, strongly consistent relational database service. It combines the benefits of relational database structure with non-relational horizontal scale, offering ACID transactions, SQL queries, and external consistency across globally distributed deployments.

Built on Google's TrueTime API and Paxos consensus algorithm, Spanner solves the previously impossible problem of achieving external consistency in a distributed system. It can scale to thousands of nodes across multiple continents while maintaining strong consistency and supporting petabytes of data with 99.999% availability.

Spanner Performance Calculator

Spanner Core Architecture

Spanner Consistency Models

-- Read with strong consistency (default)
SELECT * FROM orders WHERE user_id = @user_id;

-- All reads see globally consistent state
-- Guaranteed to see all committed writes
-- External consistency across all regions

-- Read with bounded staleness
SELECT * FROM inventory 
WITH (max_staleness_seconds = 10)
WHERE product_id = @product_id;

-- Better performance with controlled staleness
-- Good for analytics and reporting queries

-- Read-only transaction (no locks)
BEGIN TRANSACTION READ ONLY;
  SELECT SUM(amount) FROM orders WHERE date >= '2024-01-01';
  SELECT COUNT(*) FROM users WHERE created_at >= '2024-01-01';
COMMIT;

-- Perfect for analytics and reporting

Real-World Spanner Implementations

Advanced Spanner Features

Spanner Best Practices