Cache drivers (file, Redis, Memcached) in Laravel - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

What happens when you cache data using the file driver in Laravel?

Consider this Laravel code snippet that caches a value using the file cache driver:

Cache::store('file')->put('key', 'value', 600);

What is the behavior of this code?

Laravel

Cache::store('file')->put('key', 'value', 600);

A It stores the value in Memcached for 600 seconds.

B It stores the value in Redis for 600 seconds.

C It stores the value in a file inside the storage/framework/cache/data directory for 600 seconds.

D It stores the value in the database cache table for 600 seconds.

💡 Hint

Think about where the file cache driver saves data by default in Laravel.

The file cache driver stores cached data as files inside the storage/framework/cache/data directory. The number 600 means the cache expires after 600 seconds (10 minutes).

📝 Syntax

intermediate

Which code correctly retrieves a cached value from Redis in Laravel?

You want to get the cached value stored under 'user_1' using the Redis cache driver. Which code snippet is correct?

A Cache::redis()->get('user_1');

B Cache::store('redis')->get('user_1');

C Cache::get('redis', 'user_1');

D Cache::store('memcached')->get('user_1');

💡 Hint

Use the store method with the driver name to specify Redis.

The correct way to use a specific cache driver is Cache::store('driver')->get('key'). Option B uses 'redis' as the driver and gets the key correctly.

🔧 Debug

advanced

Why does caching with Memcached fail in this Laravel code?

Given this code:

Cache::store('memcached')->put('session', 'data', 300);

The cache is not storing the value as expected. What is the most likely cause?

Laravel

Cache::store('memcached')->put('session', 'data', 300);

A Memcached extension is not installed or enabled on the server.

B The cache key 'session' is reserved and cannot be used.

C The expiration time 300 is too short and ignored by Memcached.

D Laravel does not support Memcached as a cache driver.

💡 Hint

Check if the server has the required PHP extension for Memcached.

Memcached requires the PHP Memcached extension installed and enabled. Without it, Laravel cannot use Memcached and caching fails silently or throws errors.

❓ state_output

advanced

What is the output of this Laravel cache code using Redis?

Assume Redis cache is working. What does this code output?

Cache::store('redis')->put('count', 5, 60);
Cache::store('redis')->increment('count');
echo Cache::store('redis')->get('count');

Laravel

Cache::store('redis')->put('count', 5, 60);
Cache::store('redis')->increment('count');
echo Cache::store('redis')->get('count');

A 6

B 5

C null

D Error: increment method not found

💡 Hint

Increment increases the stored number by one.

The code stores 5 under 'count', then increments it by 1, so the final value is 6.

🧠 Conceptual

expert

Which cache driver is best suited for storing session data in a distributed Laravel app and why?

You have a Laravel app running on multiple servers behind a load balancer. You want to store session data in cache for fast access and sharing between servers. Which cache driver should you choose and why?

A Database, because it is the fastest cache driver for session data.

B File, because it stores data locally and is fastest for distributed apps.

C Memcached, because it stores data on disk and is persistent across server restarts.

D Redis, because it supports fast in-memory storage and shared access across servers.

💡 Hint

Think about shared access and speed for multiple servers.

Redis is an in-memory data store that supports fast access and sharing data across multiple servers, making it ideal for distributed session storage.