How do you keep a RAG system's knowledge fresh (index updates, stale data, changing documents)?
A RAG system is only as current as its index, and stale or duplicated content quietly degrades answers. The signal is an incremental pipeline with deletes, updates, and recency signals, rather than a one-time bulk load. Here is the answer.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
A RAG system is only as current as its index, and stale or duplicated content quietly degrades answers. The signal is an incremental pipeline with deletes, updates, and recency signals, rather than a one-time bulk load. Here is the answer.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.