CockroachDB vs Google Cloud Spanner: What are the differences?

Introduction

Here we will discuss the key differences between CockroachDB and Google Cloud Spanner, two popular distributed SQL databases.

1. Consistency Model: CockroachDB uses strict serializable isolation, which ensures that all transactions are executed serially without any interference, ensuring a high level of consistency. On the other hand, Google Cloud Spanner uses externally consistent reads, which means that transactions may observe intermediate states of other concurrent transactions, providing a balance between consistency and performance.

2. Scaling: CockroachDB offers a transparent and automatic sharding mechanism, allowing it to scale horizontally by distributing data across multiple nodes. This enables CockroachDB to handle high write and read workloads efficiently. In contrast, Google Cloud Spanner uses a different approach where scaling is managed automatically by Google's infrastructure without requiring explicit sharding. This allows Spanner to scale horizontally without the need for manual intervention.

3. Multi-Region Replication: CockroachDB supports multi-region replication, allowing data to be replicated across different geographical regions for improved availability and disaster recovery. This feature ensures that even if an entire region goes offline, data remains accessible from other regions. Google Cloud Spanner also offers multi-region replication, with the ability to distribute data across multiple regions globally for strong consistency and high availability.

4. Query Language: CockroachDB uses SQL as its query language, making it easier for developers familiar with traditional relational databases to work with. It also supports distributed SQL queries and transactions across multiple nodes. On the other hand, Google Cloud Spanner uses a SQL-like query language called Spanner SQL, which is based on standard SQL but includes extensions for distributed queries and schema evolution.

5. Strong Consistency vs. Availability: CockroachDB prioritizes strong consistency, ensuring that all read and write operations are consistent and coherent. This ensures that data is always accurate and up-to-date but can come at the cost of increased latency and limited availability under certain conditions. Google Cloud Spanner, on the other hand, prioritizes availability and scalability while providing externally consistent reads. This allows Spanner to deliver high performance and availability at the expense of potentially observing intermediate states during concurrent operations.

6. Deployment: CockroachDB can be deployed on-premises, in private or public clouds, or as a managed service provided by Cockroach Labs. This provides flexibility and choice for organizations to use the deployment option that best suits their needs. Google Cloud Spanner, as the name suggests, is a fully managed service offered by Google Cloud. It is tightly integrated with other Google Cloud services and simplifies the management and operation of the database infrastructure.

In Summary, CockroachDB focuses on strong consistency, offers transparent scaling, and provides flexibility in deployment options. On the other hand, Google Cloud Spanner prioritizes availability and scalability, uses automated scaling, and offers tight integration with Google Cloud services.