Warm up with window ranking leaderboard diagnostic drill

sqlEASYSQL

Warm up with window ranking leaderboard diagnostic drill

Easy SQL arena: RANK, ROW_NUMBER, partitions, and deterministic tie breakers

XP reward

150

Coins

Target time

48m

A learner is about to attempt the full window ranking leaderboard arena. Build a smaller but realistic diagnostic that exposes whether they understand RANK, ROW_NUMBER, partitions, and deterministic tie breakers. You are working inside an analytics warehouse, and the arena only clears when the result is safe, deterministic, and explainable.

Learning objective

Learn to apply RANK, ROW_NUMBER, partitions, and deterministic tie breakers in an analytics warehouse while explaining the invariant, safety constraints, and hidden edge cases.

Mission order

submissions(user_id, category, xp, submitted_at, status). Include one normal case, one malformed case, and one ordering or safety edge case. Implement the direct solution first, then document the one edge case that can break it. Submit the solution plus enough reasoning to pass hidden edge cases.

Visible checks

returns read-only result set

Expected: no mutation statements

uses deterministic ordering

Expected: stable review output

Clear requirements

Demonstrates RANK, ROW_NUMBER, partitions, and deterministic tie breakers
Handles the visible sample and hidden edge cases
Keeps output deterministic and explainable
Stays read-only

Secure validation contract

Judge type

SQL

Complexity target

Readable single-pass aggregate or join

SQL schema

submissions(user_id, category, xp, submitted_at, status). Include one normal case, one malformed case, and one ordering or safety edge case.

Workspace

SQL query console

ready

sqlsafe mock judge

Charging editor core

Enter Immersive

Test Results

Run the visible checks when your first pass is ready.

Clear Protocol

1Read the scenario and restate the expected output shape.

2Run visible checks before chasing hidden edge cases.

3Use Genie for one nudge if stuck, then explain the invariant.

4Submit only when the result is deterministic and safe.

Rewards

150

Coins

Mission Route

Previous Next

Back to catalog

Hints

Hints are metered and logged for No Hint Hero runs.

Genie Mentor Core

Hint protocol / contextual guardrails active

Progressive hints

Failed-test aware

Solution guarded

Mission: sql-easy-window-ranking-diagnostic0 attempts0 failed tests0 hints used

Progressive hint depth

Genie: Genie online. I use your mission, attempts, failed tests, hints, and path context to coach the next rep without dumping answers first.

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sqlEASYSQL