Ghosts in the Ledger
An easy Data Modeling mock interview question on DataDriven, with an AI interviewer who asks follow-up questions and a hire or no-hire decision at the end.
- Domain
- Data Modeling
- Difficulty
- easy
- Seniority
- L4
Interview Prompt
We run a B2B SaaS platform that bills customers monthly. Each invoice pairs a header carrying the billing period and running status with a variable set of charges for subscription tiers, usage overages, and one-time fees, where every charge locks in the price that was in effect when the bill was issued. Finance needs to see what each customer still owes as invoices age past their due date.
Summary
Invoices go out, partial payments trickle in, and some customers are three months overdue.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Draw your data model on the schema canvas: tables, keys and relationships
- Answer the interviewer's follow-up questions, then get a hire or no-hire decision