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."
Clean and Merge Housing Data
This question evaluates data cleaning, type coercion, robust merge operations, and missing-data imputation skills within tabular datasets, emphasizing...
Calculate Cohort Retention
You are given two tables: users - user_id BIGINT PRIMARY KEY - signup_ts TIMESTAMP user_events - user_id BIGINT - event_ts TIMESTAMP - event_name VARC...
Analyze spend cohort and source shifts
You work on an ads platform. Assume all timestamps are in UTC. Interpret last year as calendar year 2023 and this year as calendar year 2024. Tables: ...
Find least active countries
This question evaluates proficiency in SQL-based data manipulation and analytics, focusing on time-based filtering, distinct aggregation, grouping, th...
Analyze document collaboration from CSV logs
You are given two CSV files exported from a document collaboration product. Data 1) doc_access.csv Each row represents a user accessing (viewing/editi...
Convert multi-currency revenue to USD totals
This question evaluates a candidate's competency in converting multi-currency revenue into USD totals by aligning event dates with FX rates, handling ...
Write SQL for seller and category metrics
This question evaluates proficiency in SQL data manipulation—principally joins, aggregations, grouping, filtering, date arithmetic, and safe handling ...
Compute multi-account user distribution and unread pct
You are working on a product where a user can have multiple accounts, and each account can receive notifications. Tables Assume the following schemas:...
Compute article-type diversity per user and histogram
You track article views and article metadata. Tables article_views - user_id INT - article_id INT - view_date DATE articles - article_id INT (PK) - ar...
Find top countries by population per continent
Table world_population - continent VARCHAR - country VARCHAR - population BIGINT Assume each row is a country’s latest population and (continent, coun...
Build the auction status table
This question evaluates SQL data manipulation skills and relational querying competencies, including joins, aggregations, NULL handling, and identifyi...
Compute ads revenue by geography in SQL
You have ad delivery logs for a shop-ads system. Tables ad_impressions - impression_id STRING (PK) - ts TIMESTAMP (UTC) - user_id STRING - shop_id STR...
Calculate Ultimate Loss by Policy Term
You work with insurance policy-term loss data. For a given policy term, its ultimate loss is defined as the sum of losses from the current term and al...
Write SQL for CTR and revenue
Write SQL for the following two tasks. Problem 1: CTR during peak vs. non-peak hours You are given three tables: - ads(ad_id BIGINT, advertiser_id BIG...
Write SQL for influence score and follower growth
You are working on a social product with these tables: Tables / Schemas users - user_id BIGINT (PK) - created_at TIMESTAMP posts - post_id BIGINT (PK)...
Find top-5 most similar rows across datasets
You can solve this in SQL or Python. You are given two datasets with the same feature columns: Tables target_rows (rows you want to match) - target_id...
Compute active ad revenue by creation source
You work on an ads platform and need to report active ad revenue broken down by the ad’s creation source. Tables ads - ad_id BIGINT PK - advertiser_id...
Write monthly customer and sales SQL queries
You are analyzing a food-delivery marketplace. Tables Assume the following schema (you may add minor helper CTEs as needed): orders - order_id (BIGINT...
Find top-paid employee per department
Given the following tables: 1) employees - employee_id INT PRIMARY KEY - employee_name VARCHAR 2) employee_department - employee_id INT - department_i...
Pivot daily users and revenue by platform
You are given transaction-level data and need daily aggregates by platform. Input (Pandas DataFrame) df with columns: - file_date (DATE or string pars...