Context

Finance and operations teams often need a repeatable way to compare budgeted spend against actual spend each month. Interviewers ask this to assess whether you can translate a business reporting process into clear SQL logic.

Core question

Walk through how you would conduct a monthly budget variance analysis for a large department using SQL. In your answer, explain:

1. How you would structure the source data for budgets and actuals
2. How you would aggregate data to the monthly level
3. How you would calculate dollar and percentage variance
4. How you would handle missing values, late postings, and unusual transactions
5. How you would present the final output so finance leaders can review it quickly

Scope guidance

Keep the answer practical and SQL-focused. The interviewer is not looking for advanced optimization or complex modeling here; they want a clean process, sensible assumptions, and a clear explanation of the core SQL steps and checks.