“并行”查询是指并行执行或同时执行的查询,以最大限度地提高获取并发性。
当并行查询的数量不变时,使用并行查询无需额外努力。只需并排使用任意数量的 TanStack Query 的 useQuery 和 useInfiniteQuery 钩子即可!
<script setup lang="ts">
// 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,
})
</script>
<script setup lang="ts">
// 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,
})
</script>
如果需要执行的查询数量在渲染之间发生变化,则不能使用手动查询,因为这会违反钩子的规则。相反,TanStack Query 提供了 useQueries 钩子,您可以使用它来动态并行执行任意数量的查询。
useQueries 接受一个选项对象,其中包含一个 queries 键,该键的值是查询对象数组。它返回一个查询结果数组
const users = computed(...)
const queries = computed(() => users.value.map(user => {
return {
queryKey: ['user', user.id],
queryFn: () => fetchUserById(user.id),
}
})
);
const userQueries = useQueries({queries: queries})
const users = computed(...)
const queries = computed(() => users.value.map(user => {
return {
queryKey: ['user', user.id],
queryFn: () => fetchUserById(user.id),
}
})
);
const userQueries = useQueries({queries: queries})