When managing state in a React app, we often come across two popular tools: Redux and TanStack Query (formerly known as React Query). Both are incredibly useful, but they serve different purposes. Let’s dive into the basics to see when you’d choose one over the other.
What is Redux?
Redux is a state management library that helps organize and manage your app's state, especially when it becomes large and complex. With Redux, we store data in a centralized place called the store, making it accessible to any component that needs it. It works well for managing global state, like a shopping cart or user authentication, which multiple parts of your app need to access.
How Redux Works:
Actions: Describe an event or change, like adding an item to the cart.
Reducers: Take the current state and an action, and return the new state.
Store: Holds all the state, which components can access as needed.
Redux is like a container for your app’s local data that changes often and affects multiple parts of the UI.
What is TanStack Query?
TanStack Query is a library focused on managing server state (data fetched from a server). It’s great for handling asynchronous data, like fetching, caching, and updating data from APIs. This makes it ideal for tasks where you need to load and sync data from an external source, like a database or API.
How TanStack Query Works:
Fetching Data: Automatically fetches data and keeps it up-to-date when something changes.
Caching: Saves the fetched data in a cache, so it doesn’t need to be re-fetched unless necessary.
Automatic Refetching: Automatically refetches data when it becomes “stale” (old or outdated), ensuring the UI shows the latest data.
With TanStack Query, you don’t have to worry about manually refetching or storing data from an API – it handles that automatically.
Key Differences Between TanStack Query and Redux
Feature | Redux | TanStack Query |
---|---|---|
Purpose | Manages local state (data within the app) | Manages server state (data from an API) |
Caching | No built-in caching | Built-in caching for API data |
Data Synchronization | Doesn’t automatically sync with a server | Automatically refetches and syncs server data |
Setup | Requires more setup (actions, reducers, store) | Simple setup; just configure queries |
State Persistence | Centralized state used across multiple components | Cached data is temporary; more focused on API |
Use Redux when:
You need to manage global state that the whole app relies on (e.g., user login, theme, cart).
You want predictable state changes with actions and reducers.
You have complex interactions between parts of your app that need to share state.
When to Use TanStack Query
Use TanStack Query when:
You need to fetch data from an API and keep it in sync.
You want automatic caching and refetching for external data.
You need to handle asynchronous data without manual refetching or storage logic.
Can I Use Both?
Yes! In fact, combining Redux and TanStack Query is common. For example:
Use Redux for local/global app state (e.g., current user, theme).
Use TanStack Query for server data (e.g., product lists, blog posts) that needs to be fetched and kept up-to-date.
Conclusion
Redux and TanStack Query are both excellent tools for state management, but they’re designed for different types of data. Redux is your go-to for managing complex app state within your UI, while TanStack Query is perfect for managing API data with caching and refetching.
By choosing the right tool for the job, you can make your app more efficient, organized, and easy to maintain. So, next time you’re setting up your app’s state, ask yourself: Is this local app state or data from a server? That’ll help guide you to the right choice!