Mode disclosure
All modes use one coherent workspace; only disclosure and guidance change. Practice mode uses a concise prompt, normal schema, optional hints, and the same local Run and Check pipeline.
Multiple Columns, Column Order, and Aliases / write query
M03-A06 - Contract checkpoint - produce three columns with exact aliases and order on a transfer table
M03-A06 - Contract checkpoint - produce three columns with exact aliases and order on a transfer table. Match exact output contracts for columns, order, and report-friendly aliases.
- Result grain
- one commerce customer row with three exact report aliases
- Exact columns
- customer_number; customer_label; sales_region
SQL editor shortcuts: Ctrl or Command Enter runs the query, Ctrl or Command Shift Enter checks it, Alt H opens the next hint, Ctrl or Command slash toggles a line comment, Ctrl or Command Shift F formats the SQL, and Escape closes transient UI.
Cursor at line 1, column 1.
Scenario
Match exact projection contracts: column count, header names, header order, aliases, and source-versus-result identifier boundaries.
Multiple Columns, Column Order, and Aliases / write query
One-sentence task
M03-A06 - Contract checkpoint - produce three columns with exact aliases and order on a transfer table. Match exact output contracts for columns, order, and report-friendly aliases.
Practice mode disclosure
Concise prompt, normal schema help, optional hints, and the same checker workspace are available.
Structured output contract
- Result grain
- one commerce customer row with three exact report aliases
- Exact columns
- customer_number; customer_label; sales_region
- Source population
- Use the prompt setup plus FROM, JOIN, WHERE, and subquery predicates as the source population. Visible rows are only examples.
- Grouping
- Do not collapse rows unless the contract explicitly asks for aggregation, distinct tuples, or set semantics.
- Ordering
- keep aliases in that exact order; order by customer_id
- Validation
- select-only; hidden deterministic variants.
Relevant tables
Time and difficulty
- Estimated time
- 9 minutes
- Difficulty
- 2/5
Objective and concepts
Practice mode keeps the prompt concise; open hints only if you choose guided help.
Assumptions, dialect notes, and common traps
- Duplicate policy
- Preserve duplicate facts unless the prompt explicitly asks for distinct tuples or set semantics.
- Null policy
- Preserve NULL, empty string, zero, and false as distinct values unless the contract says to display a fallback.
- Tie-breakers
- Use every ordering rule in the contract and end tied business metrics with deterministic secondary keys when needed.
- Zero-related entities
- Do not invent zero rows unless the contract asks for preserved parents, missing entities, or complete periods.
- Numeric tolerance
- Use exact semantic comparison unless the activity explicitly declares a numeric tolerance.
Opened hints
No hints opened yet.