Walk the Top-N-Per-Group Decision Path Without Duplicating Rows
Navigate the main design decisions in a top-N-per-group query using windows instead of brittle aggregate joins.
The request The team needs the top 2 renewal opportunities per account, but ties are causing duplicate rows when the summary is joined back to the detail table. The fix is not DISTINCT. The fix is ranking at the correct grain. Framework Partition → Rank → Outer filter Top-N-per-group works best when you keep the detailed rows intact and layer ranking over them. Choose the peer set with partition by, choose the tie rule with the ranking function and tie-breaker, then filter in a wrapping query because window results are available after WHERE and GROUP BY. Anti-pattern Aggregate first, then…
Sign up free — one personalized lesson every day, matched to your role and goals.
Already have an account? Sign in