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."
Compute churn with re-subscriptions
This question evaluates proficiency in event-time data manipulation, temporal aggregation, and subscription-state logic for computing conversion and r...
Design Schema for Accurate Subscription State Tracking
subscription_events +----------+---------------------+-----------+-----------+ | user_id | event_ts | event_type| plan_type | +----------+...
Write SQL for multi-account metrics
This question evaluates proficiency in SQL for multi-table aggregation, grouping, joins, and conditional counting within a user-account-notification s...
Compute specialty spend share and top age band
You are given healthcare claims data split across member tables. Tables Assume the following schemas (types may be adapted to your SQL dialect): mem1 ...
Analyze spend and creation-source shifts
This question evaluates a data scientist's competency in SQL-based data manipulation, time-series aggregation, joins, and metric computation for analy...
Justify and harden your analytics and BI stack
List your current analytics tech suite end-to-end (ingestion, storage/warehouse, transformation, orchestration, catalog/lineage, experimentation platf...
Analyze DoorDash Orders: High-Frequency Customers, Top Spenders, MoM Sales & Bottom-Percentile Reach
orders +-------------+-------------+---------------+---------------------+ | delivery_id | customer_id | restaurant_id | order_place_time | +------...
Compute pirated-theme usage and revenue loss
This question evaluates SQL data manipulation and time-series analytics skills, focusing on interval overlap logic, aggregation of distinct entities, ...
Count Article Types Viewed
Count Article Types Viewed You are given article view events and article metadata. Table 1: article_views — one row per article view event. | Column |...
Write SQL for top categories and highly active users
You are given three tables: 1) impression Event-level table of user impressions. - impression_id BIGINT (PK) - user_id BIGINT (FK → user.user_id) - pi...
Find top buyer in earliest 10-year window
This question evaluates proficiency in data manipulation and analytical querying with SQL/Python, emphasizing date-based windowing, join operations, a...
Compute seller counts and vehicle share
You are given two tables: 1. listing_interactions - buyer_id BIGINT - seller_id BIGINT - event_date DATE - product_id BIGINT - listing_...
Compute a Seven-Day Rolling Average
Compute a Seven-Day Rolling Average Write one PostgreSQL SELECT statement or CTE query. Do not create, alter, or modify tables. Schema daily_metrics |...
Write SQL for post-trial conversion cohorts
Using the schema below, write SQL to compute, for users first exposed between 2025‑06‑01 and 2025‑06‑30 (inclusive), the intent‑to‑treat paid conversi...
Explain handling very large datasets
Describe a project where you ingested and processed a dataset of at least 500 million rows or 1 TB end-to-end. Detail storage formats and partitioning...
Find common friends from directed edges
You have a directed edge list that records who followed whom. A mutual “friendship” exists only if both directions appear (A→B and B→A). Schema and sa...
Analyze Thirty-Day Ad Performance with SQL
Analyze Thirty-Day Ad Performance with SQL For this practice version, use the following neutral schema. clicked is a Boolean recorded on each impressi...
Compute Each Advertiser's Share of Shop Ad Spend
Compute Each Advertiser's Share of Shop Ad Spend You have the following daily advertising table: `text ads_detail( advertiser_id, ad_id, ad_type...
Write SQL for top drivers and cancellation rates
Question You work on a rideshare / ride-hailing product that connects drivers and riders, with a focus on airport pickups. Using SQL, answer the quest...
Compute window averages and merge intervals
Compute window averages and merge intervals You are given two independent pandas tasks. 1. Centered sliding-window average - Input DataFrame df with c...