React Query - How to find out which mutation led to refetching of query

The solution Ahmed Sbai said above is good (you can use state instead of local variables), and here is another approach for you.

You can check condition based on isLoading in the object returned from useMutation().

Updated: As written in this TkDodo's blog, the "magic" is here:

If you want your mutation to stay in loading state while your related queries update, you have to return the result of invalidateQueries() from the callback.

Therefore, you won't need to use the useIsFetching() hook, too.

function App() {
  const addMutation = useMutation({
    mutationFn: (newTodo) => {
      return axios.post('/todos', newTodo)
    },
    onSuccess: () => {
      return queryClient.invalidateQueries({
        queryKey: ['todos'],
      })
    }
  })

  const updateMutation = useMutation({
    mutationFn: (id, data) => {
      return axios.patch(`/todos/${id}`, data)
    },
    onSuccess: () => {
      return queryClient.invalidateQueries({
        queryKey: ['todos'],
      })
    }
  })

  const deleteMutation = useMutation({
    mutationFn: (id) => {
      return axios.delete(`/todos/${id}`)
    },
    onSuccess: () => {
      return queryClient.invalidateQueries({
        queryKey: ['todos'],
      })
    }
  })

  return (
    <div>
      {/* ... */}
      <button
        onClick={() => addMutation.mutate(...)}
        loading={addMutation.isLoading}
      >
        Submit
      </button>

      <button
        onClick={() => updateMutation.mutate(...)}
        loading={updateMutation.isLoading}
      >
        Save changes
      </button>

      <button
        onClick={() => deleteMutation.mutate(...)}
        loading={deleteMutation.isLoading}
      >
        Delete
      </button>
    </div>
  )
}

If you want any further information, please read more in Docs.