How does React Query handle UK GDPR personal data caching?

React Query caches personal data in memory — UK GDPR considerations: (1) data is only cached while the React application is running (memory cache — not localStorage), (2) on logout: queryClient.clear() removes all cached personal data from memory, (3) staleTime configuration: set staleTime appropriately for personal data sensitivity (NHS patient data: staleTime: 0 — always fresh, never stale), (4) queryClient.invalidateQueries() on any data change — cached personal data invalidated immediately when underlying data changes. UK GDPR Article 25: do not use React Query as a long-term cache for personal data — it is an application-layer optimisation, not a data store. ClickMasters configures logout cleanup and appropriate staleTime for all NHS and FCA applications.

Should UK projects use SWR or React Query?

TanStack Query (React Query) is the right choice for most UK applications because: (1) UK enterprise applications typically have complex data fetching requirements (pagination, optimistic updates, background refetch) that SWR requires manual implementation for, (2) tRPC integration is native in React Query — if you use tRPC, use React Query, (3) NHS and FCA regulated applications benefit from React Query's explicit cache management (queryClient.invalidateQueries, queryClient.clear on logout). SWR is appropriate when: the application has simple data fetching (read-only, no mutations, few endpoints) and bundle size is critical (SWR is 14KB vs React Query 45KB). ClickMasters has not used SWR on a regulated UK project since 2022.

React Query Vs Swr Vs Apollo Uk 2026

TanStack Query (React Query) vs SWR vs Apollo Client — UK Data Fetching (2026)

Updated: February 20269 min read

🇬🇧 UK💷 GBP📊 Comparison🔒 UK GDPR⚖️ UK Law

Direct Answer

TanStack Query (React Query v5) is the UK default for data fetching in React applications: most comprehensive (server state, caching, background refetch, pagination, infinite scroll, optimistic updates), framework-agnostic (works with REST, tRPC, GraphQL), and the most widely used in UK production. SWR is right for simpler use cases where React Query's full feature set is unnecessary. Apollo Client is right exclusively for GraphQL applications. Data fetching library choice affects UK GDPR personal data caching behaviour, developer productivity, and loading state management.

Factor	TanStack Query (React Query v5)	SWR	Apollo Client
UK GDPR data caching	✅ Fine-grained cache invalidation — personal data can be purged per-key	Cache key control — manual invalidation	Apollo cache normalisation — complex personal data management
Works with REST	✅ fetch wrapper + query function	✅ fetcher function	Not designed for REST
Works with tRPC	✅ tRPC React Query integration — native	Manual adapter	Not designed for tRPC
Works with GraphQL	✅ Via custom fetcher	✅ Via custom fetcher	✅ Native — built for GraphQL
Optimistic updates	✅ Built-in — useMutation with rollback	Manual implementation	✅ Built-in for GraphQL
Infinite scroll / pagination	✅ useInfiniteQuery — built-in	Manual implementation	fetchMore — available
Background refetch (stale-while-revalidate)	✅ Configurable staleTime, refetchInterval	✅ Core feature	Available
Bundle size	Medium (~45KB)	Small (~14KB)	Large (~70KB) — worth it only for GraphQL
ClickMasters default	✅ All UK React projects	Simple data fetching (< 5 endpoints)	GraphQL-only projects