Ties, NULLs, and the RANK Trap

Concepts covered: sqlRowNumber

The canonical solution still applies. ROW_NUMBER inside a CTE, filtered to rn <= N in the outer query. The shape is unchanged. What changes at this level is how you talk about the tiebreaker. ROW_NUMBER without a deterministic tiebreaker returns arbitrary results on ties, and the interviewer will probe that. The query with the tiebreaker in place Why the multi-column ORDER BY matters Without a tiebreaker, ROW_NUMBER assigns positions arbitrarily for tied salaries. The same query on the same data can return Bob today and Carol tomorrow, depending on the engine's row order. That non-determinism is the bug that ships to production and is impossible to reproduce. The fix is a multi-column ORDER BY that includes a tiebreaker that is unique per row. Salary DESC is the primary. Hire_date ASC is t

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