Cache key strategies in Spring Boot - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a cache key in Spring Boot caching?

A cache key is a unique identifier used to store and retrieve cached data. It helps the cache know which data to return for a given request.

beginner

Why should cache keys be unique and consistent?

Unique and consistent keys ensure the cache returns the correct data every time. If keys are not unique, cached data can be overwritten or mixed up, causing errors.

intermediate

Name two common strategies to create cache keys in Spring Boot.

1. Using method parameters directly as keys.<br>2. Using a custom key generator to build keys from multiple parameters or objects.

intermediate

What is the role of a custom key generator in Spring Boot caching?

A custom key generator creates cache keys based on complex logic, like combining multiple method parameters or formatting keys for better uniqueness and readability.

advanced

How can improper cache key design affect application performance?

If cache keys are not well designed, cache hits decrease, causing more database calls and slower responses. It can also lead to stale or incorrect data being served.

What does a cache key uniquely identify in Spring Boot caching?

A The application server

B The database connection

C Cached data for a specific method call

D The user interface layout

Cache keys identify cached data related to specific method calls and their parameters.

Which of these is a good practice for cache keys?

A Use method parameters consistently

B Use random strings every time

C Use the current timestamp

D Use the user's IP address only

Using method parameters consistently ensures cache keys are unique and repeatable.

What happens if two different method calls produce the same cache key?

A Cache overwrites previous data causing errors

B Cache stores both separately

C Cache ignores the second call

D Cache creates a new cache region

Same keys cause overwriting, leading to wrong data being returned.

What is a benefit of using a custom key generator?

A It slows down caching

B It allows complex keys from multiple parameters

C It disables caching

D It encrypts cache data

Custom key generators help create meaningful keys from complex inputs.

Which is NOT a good cache key strategy?

A Combining method name and parameters

B Using a hash of parameters

C Using a custom key generator

D Using a fixed constant key for all calls

Using a fixed key causes all cached data to collide, breaking caching.

Explain why cache keys must be unique and consistent in Spring Boot caching.

Think about what happens if keys repeat or change unexpectedly.

Describe two ways to create cache keys in Spring Boot and when you might use each.

Consider simple methods versus methods with multiple or complex inputs.