Cache-aside pattern in HLD - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the Cache-aside pattern?

The Cache-aside pattern is a design where the application first checks the cache for data. If the data is missing, it loads from the database, then stores it in the cache for future requests.

beginner

In the Cache-aside pattern, who is responsible for loading data into the cache?

The application is responsible for loading data into the cache when it finds a cache miss. It fetches data from the database and then updates the cache.

intermediate

What happens when data is updated in the Cache-aside pattern?

When data is updated, the application updates the database first and then invalidates or updates the cache to keep data consistent.

intermediate

Why is the Cache-aside pattern considered scalable?

Because it reduces database load by serving repeated requests from the cache, and the cache can be scaled independently to handle more reads.

intermediate

Name one drawback of the Cache-aside pattern.

One drawback is the potential for stale data if the cache is not properly invalidated after database updates.

In the Cache-aside pattern, what does the application do on a cache miss?

A Fetch data from the database and update the cache

B Return an error to the user

C Only update the cache without fetching data

D Ignore the request

On a cache miss, the application fetches data from the database and then updates the cache for future requests.

Who manages cache invalidation in the Cache-aside pattern?

A The cache system automatically

B The database

C The application

D The user

The application is responsible for invalidating or updating the cache after data changes.

Which of these is a benefit of the Cache-aside pattern?

A Always consistent data without any stale reads

B Cache automatically updates itself without application logic

C No need to update the cache after database writes

D Reduced database load by caching frequently accessed data

The Cache-aside pattern reduces database load by caching data that is frequently read.

What is a common risk when using the Cache-aside pattern?

A Data in cache can become stale if not invalidated properly

B Cache never gets used

C Database is bypassed completely

D Cache updates happen automatically without control

If the cache is not invalidated after database updates, stale data can be served.

Which scenario best fits the Cache-aside pattern?

A When data changes every second

B When data is mostly read and rarely updated

C When cache is the only data source

D When no database is used

Cache-aside works best when data is read often but updated infrequently.

Explain how the Cache-aside pattern works from a user request to data retrieval.

Think about the steps the application takes when data is requested.

Describe how data consistency is maintained in the Cache-aside pattern when data is updated.

Focus on the order of operations during data write.