Data Scientist Data Manipulation (SQL/Python) Interview Questions
Practice 550 real Data Manipulation (SQL/Python) interview questions for Data Scientist roles. From companies including Meta, Amazon, TikTok, Capital One, DoorDash.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Write dating profile report with final reviews
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Identify country with highest sunny-day probability
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Count buggy vs non-buggy by employer
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Write SQL to verify quarterly sales decline
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Compute cohort GMV and payer rate with edge cases
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Compute video-call SQL metrics with edge cases
Use 'today' = 2025-09-01. Assume UTC timestamps. Write SQL to answer both parts below and call out how your queries handle edge cases (duplicates, fai...
Compute unconnected 60s posts and reactions averages
Given these tables and sample data, write SQL that answers both tasks below. Use today = 2025-09-01 and interpret "last/past 7 days" as the inclusive ...
Write SQL for visibility, calls, and cohort activity
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Write SQL for retention, conversion, and churn
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Write SQL to analyze response accuracy and speed
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Write SQL and Python for funnels/retention
Given the following schema and small samples, answer Parts A–C. Assume timestamps are UTC and "today" is 2025-09-01. Schema: users(id INT, country STR...
Match requests and accepts into friendships in SQL
Given two event tables, write a single SQL query (PostgreSQL) to output unique undirected friendships with the earliest valid friendship_date. Schema ...
Create and query an e-commerce schema
PostgreSQL only. 1) Create these tables with appropriate types and constraints (choose minimal correct types): products(product_id PK, name NOT NULL, ...
Write SQL to find top net-revenue products
Using the sample schema and data below, write a single SQL query that returns, for the last 7 days relative to today (use today = 2025-09-01, so the w...
Audit flight data quality from metadata
You’re given an airline on‑time dataset and a one‑page “Metadata” slide that claims: flight_date (string, local time), dep_time/arr_time (HHMM local),...
Write SQL for active counts and YTD top driver
Given the following schema and sample data, write SQL to: (a) return the total count of active riders and active drivers on the platform; (b) return t...
Model schema and query new-market readiness
Assume today is 2025-09-01. You are given (or can propose) a minimal schema to assess new-market readiness and early performance. Use the schema below...
Compute age-band spend and YoY in Georgia
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Verify subscriptions and analyze orders with SQL/Python
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Impute missing values without leakage
Given a DataFrame df with columns: user_id, event_date (datetime), country (categorical), device_type (categorical), age (numeric), income (numeric), ...