# Parallel Queries

"Parallel" queries are queries that are executed in parallel, or at the same time so as to maximize fetching concurrency.

## Manual Parallel Queries

When the number of parallel queries does not change, there is **no extra effort** to use parallel queries. Just use any number of TanStack Query's `useQuery` and `useInfiniteQuery` functions side-by-side!



```tsx
function App () {
  // The following queries will execute in parallel
  const usersQuery = useQuery(() => ({ queryKey: ['users'], queryFn: fetchUsers }))
  const teamsQuery = useQuery(() => ({ queryKey: ['teams'], queryFn: fetchTeams }))
  const projectsQuery = useQuery(() => ({ queryKey: ['projects'], queryFn: fetchProjects }))
  ...
}
```





## Dynamic Parallel Queries with `useQueries`



If the number of queries you need to execute changes, you cannot use manual querying since that would break reactivity. Instead, TanStack Query provides a `useQueries` function, which you can use to dynamically execute as many queries in parallel as you'd like.




`useQueries` accepts an **accessor that returns an options object** with a **queries key** whose value is an **array of query objects**. It returns an **array of query results**:




```tsx
function App(props) {
  const userQueries = useQueries(() => ({
    queries: props.users.map((user) => {
      return {
        queryKey: ['user', user.id],
        queryFn: () => fetchUserById(user.id),
      }
    }),
  }))
}
```