The full problem statement is available to Pro members.
preloaded fixtures
import pandas as pd
import numpy as np
runs = pd.DataFrame({
"job_name": ["bronze_ingest", "silver_clean", "gold_marts", "bronze_ingest", "train_churn", "train_churn", "gold_marts", "dashboard_refresh"],
"cluster": ["etl-nightly", "etl-nightly", "etl-nightly", "etl-nightly", "ml-training", "ml-training", "etl-nightly", "bi-serving"],
"day": ["2024-03-01", "2024-03-01", "2024-03-01", "2024-03-02", "2024-03-02", "2024-03-03", "2024-03-06", "2024-03-05"],
"duration_min": [45.0, 62.5, 30.0, 48.0, 210.0, 195.0, 35.0, 12.0],
"status": ["success", "success", "failed", "success", "success", "failed", "success", "success"],
"retries": [0, 1, 3, 0, 0, 2, 1, 0],
})
runs["day"] = pd.to_datetime(runs["day"])
tables = pd.DataFrame({
"catalog": ["bronze", "bronze", "silver", "silver", "gold", "gold"],
"table_name": ["events_raw", "clicks_raw", "events_clean", "users_clean", "daily_revenue", "churn_features"],
"size_gb": [4200.0, 980.0, 2100.0, 85.0, 12.0, 44.0],
"file_count": [180000, 64000, 9000, 1200, 300, 15000],
})
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“Small file ratio per catalog”
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Pro problem
“Small file ratio per catalog”
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