LiveQueryObserver

Defined in: packages/db/src/live-query-observer.ts:117

Internal

Wraps a resolved live-query Collection (or null for a disabled query) with the shared lifecycle every framework adapter needs: start sync on first subscribe, subscribe to changes and status transitions, expose a stable snapshot for wholesale consumers, and deliver the raw change set for granular consumers.

Input resolution (query fn / config / collection / disabled) stays in the adapter — it is framework-reactive. The observer owns everything after the input is resolved to a concrete collection.

Unstable contract for TanStack DB's official framework adapters — not a public extension point yet; may change in any release.

Type Parameters#

T#

T extends object

TKey#

TKey extends string | number

Properties#

dehydrate()#

dehydrate: () => DehydratedLiveQueryResult<T, TKey>;

Defined in: packages/db/src/live-query-observer.ts:141

Capture the ordered query result without serializing its source collections.

Returns#

DehydratedLiveQueryResult<T, TKey>

dispose()#

dispose: () => void;

Defined in: packages/db/src/live-query-observer.ts:143

Idempotent teardown.

Returns#

void

getError()#

getError: () => unknown;

Defined in: packages/db/src/live-query-observer.ts:139

The transport or preload error for this query, if it has not produced data.

Returns#

unknown

getServerSnapshot()#

getServerSnapshot: () => LiveQuerySnapshot<T, TKey>;

Defined in: packages/db/src/live-query-observer.ts:124

Stable server snapshot used by useSyncExternalStore-style adapters.

Returns#

LiveQuerySnapshot<T, TKey>

getSnapshot()#

getSnapshot: () => LiveQuerySnapshot<T, TKey>;

Defined in: packages/db/src/live-query-observer.ts:122

Stable per-revision snapshot for wholesale materialization.

Returns#

LiveQuerySnapshot<T, TKey>

isInitialRenderReady()#

isInitialRenderReady: () => boolean;

Defined in: packages/db/src/live-query-observer.ts:137

Whether a persisted fallback has already passed the network-first gate.

Returns#

boolean

preload()#

preload: () => Promise<void>;

Defined in: packages/db/src/live-query-observer.ts:133

Resolve once the collection has loaded its first data.

Returns#

Promise<void>

preloadForInitialRender()#

preloadForInitialRender: () => Promise<void>;

Defined in: packages/db/src/live-query-observer.ts:135

Resolve at network readiness or a permitted persisted fallback.

Returns#

Promise<void>

subscribe()#

subscribe: (listener) => () => void;

Defined in: packages/db/src/live-query-observer.ts:131

Subscribe to changes. The listener receives the change set (or undefined for the synthetic notify a ready collection emits on attach). Granular adapters apply the changes; wholesale adapters can ignore them and re-read getSnapshot(). Returns an unsubscribe function.

Parameters#

listener#

LiveQueryObserverListener<T, TKey>

Returns#

(): void;

Returns#

void