What is the REACT QUERY way to reuse global state?

React Query is a library for handling asynchronous data fetching and caching, enabling the reuse of global state within React applications. Below are several methods for achieving this with React Query:

1. Using Caching and State Sharing: React Query manages global state through caching mechanisms. When a data request is initiated, it first checks the cache for existing data. If found, it returns the data directly from the cache instead of making a new server request. This ensures that when multiple components request identical data, React Query efficiently reuses the cached data, reducing unnecessary network calls.

   Example: Consider multiple components needing user details. With React Query, you can create a unified query hook (e.g., useUserDetails), which internally uses useQuery to fetch data from an API. Regardless of where this hook is used in the application, identical query keys and parameters guarantee the same cached data is returned.

2. Configuring a Global Query Client: React Query allows you to set up a global QueryClient instance that oversees all queries and caching. By configuring this QueryClient at the application's root level and wrapping the entire app with QueryClientProvider, you ensure consistent caching strategies and settings across all data queries.

   Example: Configure QueryClient in the root component and wrap the application:

   javascript
   import { QueryClient, QueryClientProvider } from 'react-query';
   
   const queryClient = new QueryClient();
   
   function App() {
     return (
       <QueryClientProvider client={queryClient}>
         <MyComponent />
       </QueryClientProvider>
     );
   }

3. Synchronizing State Across Multiple Components: Using React Query's useQuery or useMutation hooks, state updates propagate automatically to all components sharing the same query. This means that when a component triggers a data update (e.g., via useMutation), all components querying that data instantly receive the latest results.

   Example: If a component updates database data using useMutation, and other components fetch the same data via useQuery, those queries automatically re-run post-update to retrieve the newest data.

In summary, React Query offers an efficient approach to reuse global state through intelligent caching and centralized query management, facilitating seamless data sharing and synchronization across components and pages while maintaining concise, high-performance code.