TanStack DB core concepts: createCollection with queryCollectionOptions, electricCollectionOptions, powerSyncCollectionOptions, rxdbCollectionOptions, trailbaseCollectionOptions, localOnlyCollectionOptions. Live queries via query builder (from, where, join, select, groupBy, orderBy, limit). Optimistic mutations with draft proxy (collection.insert, collection.update, collection.delete). createOptimisticAction, createTransaction, createPacedMutations. Entry point for all TanStack DB skills.

Query builder fluent API: from, where, join, leftJoin, rightJoin, innerJoin, fullJoin, select, fn.select, groupBy, having, orderBy, limit, offset, distinct, findOne. Operators: eq, gt, gte, lt, lte, like, ilike, inArray, isNull, isUndefined, and, or, not. Aggregates: count, sum, avg, min, max. String functions: upper, lower, length, concat, coalesce. Math: add. $selected namespace. createLiveQueryCollection. Derived collections. Predicate push-down. Incremental view maintenance via differential dataflow (d2ts).

collection.insert, collection.update (Immer-style draft proxy), collection.delete. createOptimisticAction (onMutate + mutationFn). createPacedMutations with debounceStrategy, throttleStrategy, queueStrategy. createTransaction, getActiveTransaction, ambient transaction context. Transaction lifecycle (pending/persisting/completed/failed). Mutation merging. onInsert/onUpdate/onDelete handlers. PendingMutation type. Transaction.isPersisted.

Offline transaction support for TanStack DB. OfflineExecutor orchestrates persistent outbox (IndexedDB/localStorage), leader election (WebLocks/ BroadcastChannel), retry with backoff, and connectivity detection. createOfflineTransaction/createOfflineAction wrap TanStack DB primitives with offline persistence. Idempotency keys for at-least-once delivery. Graceful degradation to online-only mode when storage unavailable. React Native support via separate entry point.

React bindings for TanStack DB. useLiveQuery hook with dependency arrays (8 overloads: query function, config object, pre-created collection, disabled state via returning undefined/null). useLiveSuspenseQuery for React Suspense with Error Boundaries (data always defined). useLiveInfiniteQuery for cursor-based pagination (pageSize, fetchNextPage, hasNextPage, isFetchingNextPage). usePacedMutations for debounced React state updates. Return shape: data, state, collection, status, isLoading, isReady, isError. Import from @tanstack/react-db (re-exports all of @tanstack/db).

SolidJS bindings for TanStack DB. useLiveQuery returns an Accessor that doubles as data access (call as function) with state/status properties. Fine-grained reactivity: signal reads MUST happen inside the query function for tracking. Config passed as Accessor (() => config). Built-in Suspense support via createResource. ReactiveMap for state. Import from @tanstack/solid-db (re-exports all of @tanstack/db).

Vue 3 bindings for TanStack DB. useLiveQuery composable with MaybeRefOrGetter query functions, ComputedRef return values for all fields (data, state, collection, status, isLoading, isReady, isError). Dependency arrays with Vue refs. Conditional queries via returning undefined/null. Pre-created collection support via ref or getter. Import from @tanstack/vue-db (re-exports all of @tanstack/db).