React Query Tutorial: Fetching Data Made Simple

React Query enhances React apps with caching, state management, and error handling, boosting API efficiency, lowering load times, and maintaining data synchronization automatically.

Highlights

Reduces redundant API calls by 70% through automatic server caching of responses.
Handles 3+ automatic retries for failed requests, ensuring reliable data fetching.
Updates data in the background every 5 minutes, keeping the UI synchronized with the server.

In the fast-moving world of custom website development, managing data effectively has become crucial for creating high-performing web applications. React Query (now known as TanStack Query) is a robust library that streamlines data fetching, caching, synchronization, and server state management in your React web app.

Whether you’re providing website development services or planning to hire a React developer, mastering React Query can greatly improve the efficiency and reliability of your React-based projects.

Features of React Query

1. Data Caching

React Query automatically stores fetched data and reuses it to prevent redundant API calls, improving both performance and user experience.

2. Error Handling

Handles API errors internally for seamless interactions with your backend.
Reduces the need for manual try-catch blocks or repetitive error-handling logic.

3. State Management

No need to manually manage server-side state using hooks like useEffect. React Query automatically tracks loading, success, and error states, keeping your app’s UI perfectly in sync with your data.

For teams providing website development services, this means faster development cycles and fewer bugs.

Prerequisites

Before diving in, make sure you meet the following requirements:

Comprehension of JavaScript syntax
Basic knowledge of the React.js framework
Understanding of APIs
React Query and Axios are installed on your computer

Navigate to your React project directory and run the following command in your terminal:

                                        npm i @tanstack/react-query axios

If you plan to hire a React developer, ensure they are comfortable with these tools as they’re foundational for modern React-based custom website development.

Set up in index.tsx or app.tsx

To make React Query available globally, you need to wrap your entire app inside a QueryClientProvider. This allows all components to share the same query client and benefit from global caching and synchronization.

Code Example

                                        import { QueryClient, QueryClientProvider } from "@tanstack/react-query";


import DisplayPosts from "./display-post";


const queryClient = new QueryClient();


function App() {
  return (
    <QueryClientProvider client={queryClient}>
      <DisplayPosts />
    </QueryClientProvider>
  );
}


export default App;

This setup is an important step in any React project, especially for developers working on dynamic website development services that require smooth API integrations.

Performing Data Fetching

The useQuery hook in React Query makes fetching and managing server data incredibly simple.
Below, we’ll use Axios to retrieve posts from an external API. If the data is still loading or an error occurs, appropriate messages are displayed; otherwise, the posts are rendered as a list.

The key you provide ('posts') acts as an identifier for caching. If another component uses the same key, React Query will serve the cached data instead of refetching it, making your app more efficient.

Code Example

                                        interface Post {
  id: number;
  title: string;
}


import axios from "axios";
import { useQuery } from "@tanstack/react-query";


const retrievePosts = async () => {
  const response = await axios.get(
    "https://jsonplaceholder.typicode.com/posts"
  );
  return response.data;
};


const DisplayPosts = () => {
  const {
    data: posts,
    error,
    isLoading,
  } = useQuery({
    queryKey: ["posts"],
    queryFn: retrievePosts,
  });


  if (isLoading) return <div>Fetching posts...</div>;
  if (error) return <div>An error occurred: {error.message}</div>;


  return (
    <ul>
      {posts?.map((post: Post) => (
        <li key={post.id}>{post?.title || "-"}</li>
      ))}
    </ul>
  );
};


export default DisplayPosts;

When you run this code in your browser, you’ll see a neatly rendered list of post titles fetched directly from the API.

This example demonstrates how React Query makes custom website development smoother by automating the complexities of data fetching and state synchronization.

On Success

Once the posts are successfully fetched, the browser will display a list of post titles like below:

sunt aut facere repellat provident occaecati excepturi optio reprehenderit

qui est esse

ea molestias quasi exercitationem repellat qui ipsa sit aut

eum et est occaecati

nesciunt quas odio

dolorem eum magni eos aperiam quia

magnam facilis autem

dolorem dolore est ipsam

nesciunt iure omnis dolorem tempora et accusantium

optio molestias id quia eum

Common Options (Keys) in TanStack React Query

queryKey = unique key (string or array ) used to identify and cache your query.
queryFn = Function that performs the actual fetch (must return a Promise).
enabled = Boolean — whether the query should automatically run (`false` to disable).
staleTime = time (ms) before data is considered stale and eligible for refetch.
cacheTime = time (ms) data stays in cache after being inactive.
refetchOnWindowFocus = Refetch when window regains focus (`true` by default).
retry = Number of retry attempts on error (default = 3).
keepPreviousData = Keeps old data while fetching new (useful for pagination).
onSuccess = Callback executed when the query successfully fetches data.
onError = Callback executed when query fails.
refetchInterval = Automatically refetch data at given time interval (ms).
keepPreviousData = Keeps old data while fetching new (useful for pagination).

Why React Query Is a Must-Have for Modern Web Apps

React Query bridges the gap between client and server data, making custom website development more scalable, maintainable, and user-friendly. If your business offers website development services, integrating React Query can reduce boilerplate code, improve performance, and create a more responsive experience UI.

For those hiring a React developer, selecting someone skilled in TanStack Query guarantees your projects are built with modern, efficient practices that follow today’s best web development standards.

Final Words

React Query (TanStack Query) revolutionizes how React developers handle server state management. It automates the complexities of data fetching, caching, and synchronization, allowing developers to focus on building features rather than managing state manually.

Whether you’re an agency offering website development services, working on custom website projects, or planning to hire a React developer, integrating React Query will streamline your workflow and improve your app’s performance.