Storing and retrieving cache in Laravel - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to store a value in the cache for 10 minutes.

Laravel

Cache::put('key', 'value', [1]);

Drag options to blanks, or click blank then click option'

A600

B6000

C10

D100

Attempts:

3 left

💡 Hint

Common Mistakes

Using 10 directly instead of seconds.

Using 6000 which is too long.

Confusing minutes with seconds.

The third parameter is the number of seconds to store the cache. 600 seconds equals 10 minutes.

2fill in blank

medium

Complete the code to retrieve a cached value by its key.

Laravel

$value = Cache::[1]('key');

Drag options to blanks, or click blank then click option'

Aget

Bsave

Cput

Dstore

Attempts:

3 left

💡 Hint

Common Mistakes

Using put which stores data.

Using store which is not a valid method.

Using save which does not exist in Cache facade.

The get method retrieves the cached value by its key.

3fill in blank

hard

Fix the error in the code to remember a value in the cache for 5 minutes.

Laravel

Cache::remember('key', [1], function() {
    return 'value';
});

Drag options to blanks, or click blank then click option'

A30

B3000

C300

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Using 3000 which is too long.

Using 30 which is too short.

Using 3 which is too short.

The second parameter is the number of seconds to remember the cache. 300 seconds equals 5 minutes.

4fill in blank

hard

Fill both blanks to check if a cache key exists and then retrieve it.

Laravel

if (Cache::[1]('key')) {
    $value = Cache::[2]('key');
}

Drag options to blanks, or click blank then click option'

Ahas

Bget

Cput

Dexists

Attempts:

3 left

💡 Hint

Common Mistakes

Using put instead of has or get.

Using exists which is not a Laravel Cache method.

The has method checks if the cache key exists. The get method retrieves the value.

5fill in blank

hard

Fill all three blanks to store a value forever and then retrieve it with a default fallback.

Laravel

$value = Cache::[1]('key', 'default');
Cache::[2]('key', 'value');
Cache::[3]('key', 'value');

Drag options to blanks, or click blank then click option'

Aget

Bforever

Cput

Dremember

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up put and forever.

Using remember incorrectly here.

get retrieves the value with a default fallback. forever stores the value permanently. put stores the value temporarily.

Practice

1. What does the Cache::put('key', 'value', 60) method do in Laravel?

easy

A. Stores 'value' permanently in cache without expiration

B. Retrieves 'value' from cache with 'key' and expires in 60 seconds

C. Deletes the cache entry with 'key' after 60 minutes

D. Stores 'value' in cache under 'key' for 60 minutes

Solution

1. Step 1: Understand Cache::put method

   The Cache::put method stores data in the cache with a key and expiration time in minutes.

2. Step 2: Analyze the parameters

   Here, 'key' is the cache key, 'value' is the data stored, and 60 means it expires after 60 minutes.

3. Final Answer:

   Stores 'value' in cache under 'key' for 60 minutes -> Option D

4. Quick Check:

   Cache::put stores with expiration = A [OK]

Hint: Cache::put stores with minutes expiry, not seconds [OK]

Common Mistakes:

• Confusing expiration time units (seconds vs minutes)
• Thinking Cache::put retrieves data
• Assuming Cache::put stores data permanently

2. Which of the following is the correct syntax to retrieve a cached value with a default fallback in Laravel?

easy

A. Cache::get('key', 'default')

B. Cache::retrieve('key', 'default')

C. Cache::fetch('key', 'default')

D. Cache::find('key', 'default')

Solution

1. Step 1: Identify Laravel cache retrieval method

   Laravel uses Cache::get to retrieve cached data safely.

2. Step 2: Check method parameters

   The second parameter is the default value returned if the key is not found.

3. Final Answer:

   Cache::get('key', 'default') -> Option A

4. Quick Check:

   Cache::get with default = A [OK]

Hint: Use Cache::get to retrieve with default fallback [OK]

Common Mistakes:

• Using non-existent methods like retrieve or fetch
• Forgetting the default fallback parameter
• Using Cache::put instead of Cache::get

3. What will be the output of this Laravel code snippet?

Cache::put('count', 5, 10);
$value = Cache::get('count', 0);
echo $value;

medium

A. 0

B. null

C. 5

D. Error

Solution

1. Step 1: Store value in cache

   The code stores the integer 5 under the key 'count' with expiration 10 minutes.

2. Step 2: Retrieve value from cache

   Then it retrieves 'count' with default 0. Since the key exists, it returns 5.

3. Final Answer:

   5 -> Option C

4. Quick Check:

   Cache::get returns stored value if exists = B [OK]

Hint: Cache::get returns stored value, not default if key exists [OK]

Common Mistakes:

• Assuming default value is always returned
• Confusing expiration time with immediate deletion
• Expecting null or error instead of stored value

4. Identify the error in this Laravel cache usage:

Cache::put('user', 'Alice');
$value = Cache::get('user');
echo $value;

medium

A. Cache::put requires expiration time as third argument

B. Cache::get requires a default value parameter

C. Cache::put key must be numeric

D. Cache::get cannot be used without Cache::forever

Solution

1. Step 1: Check Cache::put usage

   Cache::put requires three parameters: key, value, and expiration time in minutes.

2. Step 2: Identify missing expiration

   The code misses the expiration time, so it will cause an error or unexpected behavior.

3. Final Answer:

   Cache::put requires expiration time as third argument -> Option A

4. Quick Check:

   Cache::put needs expiration time = D [OK]

Hint: Always provide expiration time with Cache::put unless using forever [OK]

Common Mistakes:

• Omitting expiration time in Cache::put
• Thinking Cache::get always needs default
• Believing keys must be numeric

5. You want to store a user's settings permanently in cache and then remove them later. Which sequence of Laravel cache methods is correct?

hard

A. Cache::store('settings', $data); Cache::remove('settings');

B. Cache::forever('settings', $data); Cache::forget('settings');

C. Cache::put('settings', $data, 0); Cache::delete('settings');

D. Cache::save('settings', $data); Cache::clear('settings');

Solution

1. Step 1: Store data permanently

   Use Cache::forever to store data without expiration.

2. Step 2: Remove cached data

   Use Cache::forget to delete the cached key when needed.

3. Final Answer:

   Cache::forever('settings', $data); Cache::forget('settings'); -> Option B

4. Quick Check:

   Permanent store + forget = C [OK]

Hint: Use forever to store permanently, forget to delete [OK]

Common Mistakes:

• Using wrong method names like delete or remove
• Passing 0 as expiration to put for permanent storage
• Confusing Cache::store or Cache::save as valid methods