Problem Statement
Explain the tag-based cache invalidation system in RTK Query with an example.
Explanation
RTK Query uses a tag-based system where queries declare what tags they provide using providesTags, and mutations declare what tags they invalidate using invalidatesTags, creating automatic relationships between data operations. For example, a getPosts query might provide tags Posts and each individual Post with ID, while a createPost mutation invalidates the Posts list tag to trigger a refetch. Tags can be simple strings for entire collections or objects with type and id for individual items, enabling granular control like invalidating only specific posts or all posts in a category. This declarative approach eliminates manual refetch logic and keeps your UI synchronized with backend state automatically.
