Explain the difference between RANGE and ROWS window frames, and when named windows help.
Two queries that look identical apart from ROWS vs RANGE return different numbers, and most candidates cannot explain why. The signal is knowing RANGE groups by value (peers) while ROWS counts physical rows.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
Two queries that look identical apart from ROWS vs RANGE return different numbers, and most candidates cannot explain why. The signal is knowing RANGE groups by value (peers) while ROWS counts physical rows.
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.
