LiveQueryObserver

Defined in: packages/db/src/live-query-observer.ts:123

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:147

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:149

Idempotent teardown.

Returns

void

getError()

getError: () => unknown;

Defined in: packages/db/src/live-query-observer.ts:145

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:130

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:128

Stable per-revision snapshot for wholesale materialization.

Returns

LiveQuerySnapshot<T, TKey>

isInitialRenderReady()

isInitialRenderReady: () => boolean;

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

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:139

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:141

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:137

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