This code snippet very briefly illustrates the 3 core concepts of React Query:
If you're looking for a fully functioning example, please have a look at our simple codesandbox example
import {
useQuery,
useMutation,
useQueryClient,
QueryClient,
QueryClientProvider,
} from '@tanstack/react-query'
import { getTodos, postTodo } from '../my-api'
// Create a client
const queryClient = new QueryClient()
function App() {
return (
// Provide the client to your App
<QueryClientProvider client={queryClient}>
<Todos />
</QueryClientProvider>
)
}
function Todos() {
// Access the client
const queryClient = useQueryClient()
// Queries
const query = useQuery({ queryKey: ['todos'], queryFn: getTodos })
// Mutations
const mutation = useMutation({
mutationFn: postTodo,
onSuccess: () => {
// Invalidate and refetch
queryClient.invalidateQueries({ queryKey: ['todos'] })
},
})
return (
<div>
<ul>{query.data?.map((todo) => <li key={todo.id}>{todo.title}</li>)}</ul>
<button
onClick={() => {
mutation.mutate({
id: Date.now(),
title: 'Do Laundry',
})
}}
>
Add Todo
</button>
</div>
)
}
render(<App />, document.getElementById('root'))
import {
useQuery,
useMutation,
useQueryClient,
QueryClient,
QueryClientProvider,
} from '@tanstack/react-query'
import { getTodos, postTodo } from '../my-api'
// Create a client
const queryClient = new QueryClient()
function App() {
return (
// Provide the client to your App
<QueryClientProvider client={queryClient}>
<Todos />
</QueryClientProvider>
)
}
function Todos() {
// Access the client
const queryClient = useQueryClient()
// Queries
const query = useQuery({ queryKey: ['todos'], queryFn: getTodos })
// Mutations
const mutation = useMutation({
mutationFn: postTodo,
onSuccess: () => {
// Invalidate and refetch
queryClient.invalidateQueries({ queryKey: ['todos'] })
},
})
return (
<div>
<ul>{query.data?.map((todo) => <li key={todo.id}>{todo.title}</li>)}</ul>
<button
onClick={() => {
mutation.mutate({
id: Date.now(),
title: 'Do Laundry',
})
}}
>
Add Todo
</button>
</div>
)
}
render(<App />, document.getElementById('root'))
These three concepts make up most of the core functionality of React Query. The next sections of the documentation will go over each of these core concepts in great detail.
“This course is the best way to learn how to use React Query in real-world applications.”—Tanner LinsleyGet the course