Your application takes an input from a user and publishes it to the user's contacts.
This input is stored in a table in Cloud Spanner.
Your application is more sensitive to latency and less sensitive to consistency.
How should you perform reads from Cloud Spanner for this application?
Click on the arrows to vote for the correct answer
A. B. C. D.D.
https://cloud.google.com/solutions/best-practices-cloud-spanner-gaming-databaseIn this scenario, the application is more sensitive to latency and less sensitive to consistency. This means that the priority is to minimize the response time of the application, even if it means sacrificing consistency to some extent.
Option A: Perform Read-Only transactions Read-only transactions are useful when the application only needs to read data from the database, without the need for consistency guarantees. However, since the application is publishing user data to their contacts, it implies that write operations are also being performed. Therefore, this option is not ideal for this scenario.
Option B: Perform stale reads using single-read methods Stale reads involve reading data that may not reflect the latest changes made to the database. While this can lead to reduced consistency, it can also improve the latency of the application. Single-read methods, such as Read() or ReadUsingIndex(), are useful for scenarios where the application needs to retrieve data quickly without locking or modifying the data. However, since the application is performing write operations, stale reads may result in publishing outdated information to the user's contacts. Therefore, this option is also not ideal for this scenario.
Option C: Perform strong reads using single-read methods Strong reads guarantee that the read operation will return the latest committed version of the data. This ensures consistency but may come at the cost of increased latency. Since the application is more sensitive to latency, strong reads may not be the best choice. Therefore, this option is not ideal for this scenario.
Option D: Perform stale reads using read-write transactions This option is similar to option B, but instead of using single-read methods, read-write transactions are used. Read-write transactions can be used to perform read and write operations in a single transaction. In this case, the transaction would read the user's input and publish it to the user's contacts. While the read may be stale, the write operation will still be consistent, ensuring that the contacts receive the latest information. This option balances latency and consistency, making it the best choice for this scenario.
Therefore, the answer is D. Perform stale reads using read-write transactions.