Interview Q&A / System Design
System Design interview questions
Caching, scaling, databases and classic design problems for beginners.
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- How does the cache-aside pattern work?
The application checks the cache first. On a miss it reads the database, stores the result in the cache and returns it. On writes it updates the database and removes or updates the cache entry.
BeginnerQuick answer1 min read - What is the difference between write-through and write-back caching?
Write-through writes to the cache and the database together before replying, so data is safe but writes are slower. Write-back writes to the cache first and flushes to the database later, which is faster but can lose data on a crash.
IntermediateQuick answer1 min read