Paste a SELECT query below. The builder checks it for syntax errors and unknown tables/columns against DAWN's database, tells you in plain English what it will actually return, and flags common mistakes - before it goes to the developer for review.
Your query is never run. SQL Server only describes it (parses it and works out the output columns) using a read-only login, so nothing in the database is changed or even read as rows. This is a structural check, not a guarantee that the report is clinically or logically correct - a developer still reviews it.