upstream-tanstack-query/docs/framework/lit/reference/functions/keepPreviousData.md

id, title

id	title
keepPreviousData	keepPreviousData

function keepPreviousData<T>(previousData): T | undefined;

Defined in: packages/query-core/src/utils.ts:493

Intended to be passed as a query's placeholderData option, for example placeholderData: keepPreviousData. Instead of resetting the query's data to undefined while a new query key is fetching, it keeps displaying the previously fetched data until the new data arrives.

Type Parameters

T

T

Parameters

previousData

T | undefined

Returns

T | undefined

Example

new QueryObserver(queryClient, {
  queryKey: ['posts', page],
  queryFn: () => fetchPosts(page),
  placeholderData: keepPreviousData,
})