MMKV for fast storage in React Native - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is MMKV in React Native?

MMKV is a fast, efficient key-value storage library for React Native apps, designed to store data quickly and persistently on the device.

intermediate

Why use MMKV instead of AsyncStorage?

MMKV is faster and more efficient than AsyncStorage because it uses mmap for memory mapping, reducing read/write latency and improving app performance.

beginner

How do you store a string value using MMKV in React Native?

Use the set method: mmkv.set('key', 'value'); This saves the string 'value' under the key 'key' in fast storage.

beginner

How do you retrieve a stored value from MMKV?

Use the getString method: const value = mmkv.getString('key'); This fetches the string stored under 'key'.

intermediate

What is a key benefit of MMKV's storage method?

MMKV uses memory mapping (mmap) which allows fast access to data without loading the entire file into memory, saving time and battery.

What type of storage does MMKV provide in React Native?

A Key-value storage

B Relational database

C File system storage

D Cloud storage

MMKV provides fast key-value storage for storing small pieces of data efficiently.

Which method stores a string value in MMKV?

A mmkv.saveString()

B mmkv.set()

C mmkv.put()

D mmkv.store()

The set() method is used to store values in MMKV.

How do you retrieve a string value from MMKV?

A mmkv.getString()

B mmkv.fetch()

C mmkv.read()

D mmkv.loadString()

The getString() method fetches a stored string value from MMKV.

What makes MMKV faster than AsyncStorage?

A It uses SQLite internally

B It stores data in the cloud

C It uses memory mapping (mmap)

D It compresses data before saving

MMKV uses mmap to access data quickly without loading entire files.

Which of these is NOT a feature of MMKV?

A Fast read/write

B Key-value API

C Persistent storage

D Supports relational queries

MMKV does not support relational queries; it is a key-value store.

Explain how MMKV improves storage speed in React Native apps.

Think about how MMKV accesses data differently than traditional storage.

Describe the basic steps to save and retrieve a string using MMKV in React Native.

Focus on the methods used for storing and fetching data.