The full problem statement is available to Pro members.
preloaded fixtures
import pandas as pd
subscriptions = pd.DataFrame({
"account": ["a1", "a2", "a3", "a4", "a1", "a2", "a3", "a5"],
"month": ["2024-02", "2024-02", "2024-02", "2024-02", "2024-03", "2024-03", "2024-03", "2024-03"],
"mrr": [100.0, 200.0, 50.0, 80.0, 150.0, 200.0, 20.0, 75.0],
})
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Pro problem
“MRR movement breakdown”
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Pro problem
“MRR movement breakdown”
This is one of the real interview questions in Pro. Try Pro free for 7 days to unlock it and everything below:
- 293 interview-grade problems across SQL, Python & pandas
- 104+ real-world SQL problems: SaaS retention, fintech ledgers, supply chain, recursive CTEs
- 18 company interview packs (Amazon, Meta, Google, Uber and more)
- AI "explain my mistake" tutor and mock interviews
- Use QueryLab inside Claude, Cursor & other AI assistants
// built for real interview rounds
Practice the patterns 18 top companies test
329 problems · 36 free forever · 293 unlocked with Pro
Card required. Then $12/month. Cancel before your trial ends and you pay nothing.
or keep practicing free problems →Secure checkout by Paddle · instant access · cancel anytime from your account