Follow these best practices with React Query to keep your data fetching efficient and maintainable:

• Use a consistent array structure for query keys, including all relevant parameters and avoiding non-serializable values;
• Set appropriate staleTime and cacheTime to balance freshness and performance;
• Use targeted query invalidation, not global, to keep UI in sync without extra network requests;
• Transform data with the select option to reduce extra state;
• For large datasets, use paginated or infinite queries;
• Minimize unnecessary refetches with enabled flags and batch invalidations;
• Prefetch data you'll need soon and avoid duplicate queries for the same resource.

React Query is powerful but can cause issues if misused. Unstable query keys result in cache misses and repeated requests—always keep keys stable and consistent. Avoid global invalidation to prevent unnecessary refetches; target specific queries instead. Setting inappropriate staleTime can lead to either stale data or too many fetches, so adjust it based on how often your data changes. Always handle error states and do not rely only on default retry logic. Never store client state like form inputs in React Query; it is meant for server state only.