Challenge your knowledge of distributed database systems and relational cloud solutions with this quiz on essential concepts of Cloud Spanner and Cloud SQL. Enhance your understanding of scalability, consistency, availability, and use cases related to these foundational cloud data services.
Which key feature distinguishes distributed relational databases like Cloud Spanner from traditional single-instance SQL databases in terms of scalability?
Explanation: Horizontal scalability across regions allows distributed relational databases to grow seamlessly by adding more nodes, often across multiple geographic locations. Fixed storage limits per server restrict growth and are characteristic of many traditional databases. Manual sharding is commonly needed for scaling older systems, but not for modern distributed solutions. Supporting only non-relational data models describes NoSQL databases rather than relational ones.
In a scenario where multiple users need to see the most up-to-date data instantly after a transaction, which consistency model would be most appropriate?
Explanation: Strong consistency guarantees that all users see the most recent and committed data immediately, making it the best choice when immediate accuracy is required. Eventual consistency may delay data visibility, which can lead to outdated information for some users. Session consistency ensures consistency during a single user's session, not across all users. Causal consistency only guarantees order of related operations, not immediate global visibility.
What advantage does automatic multi-zone replication in managed SQL systems provide when running critical inventory applications?
Explanation: Automatic multi-zone replication reduces downtime by seamlessly redirecting operations if one location experiences a failure, which is vital for applications like inventory systems. Manual configuration of failover is not required with automatic replication. Restricting to a single write location limits availability and is not an advantage. Customers are relieved from managing underlying networking, as the provider handles it.
When migrating a large, on-premises transactional database to a managed SQL service, which factor is most important to ensure a smooth transition?
Explanation: Ensuring schema and SQL compatibility allows the database structure and queries to function similarly after migration, reducing errors and rework. Managed relational services do not focus on NoSQL data, so this is not relevant. Eventual consistency may not be suitable for transactional requirements. While some procedures might need adjustments, a mandatory rewrite is often not necessary.
A global e-commerce platform needs high availability, automatic scaling, and strong consistency for transactions. Which type of cloud database architecture is most suitable for this scenario?
Explanation: A globally-distributed relational database offers built-in high availability, scaling across multiple regions, and strong transactional support, making it ideal for a global e-commerce system. A local, single-instance SQL database cannot provide global high availability or automatic scaling. Document-oriented NoSQL databases can handle scale but often lack strong consistency or relational features. In-memory key-value stores are fast but not suited for transactionally consistent, persistent data.