Data Manipulation (SQL/Python) Interview Questions
Practice 653 real Data Manipulation (SQL/Python) interview questions for 2026. Covers companies like Meta, Amazon, TikTok, DoorDash, and Capital One. Real questions from actual interviews with detailed solutions — designed for focused interview preparation for data analysts, data scientists, and data engineers who must move fluidly between SQL and Python during live screens and take-home tasks. These questions emphasize practical skills: writing correct, efficient SQL (joins, GROUP BY, window functions, CTEs, NULL handling, and performance-aware predicates) and idiomatic Python/Pandas solutions (vectorized transforms, merges, reshaping, datetime handling, and robust data-cleaning). Interviewers evaluate correctness, edge-case reasoning, runtime and memory tradeoffs, reproducibility, and clear communication of assumptions. Expect timed whiteboard-style queries, pair-programming in a shared editor, and take-home notebooks. To prepare, practice translating SQL ↔ Pandas, explain results aloud, time-box exercises, test edge cases, and review common pitfalls such as NULL semantics, grouping logic, off-by-one errors, and inefficient joins.
"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 ARPDAU/ARPPU by country
Using only the two tables below, write a single SQL query that returns, for each day and country in the last 7 days inclusive (2025-08-26 through 2025...
Write SQL to flag suspect payments and chargebacks
Assume today is 2025-09-01. Using only CASE WHEN and JOINs (no window functions required), write a single SQL query that produces, for each user with ...
Fix dash dates and aggregate watch time
You receive a CSV of ad viewing logs where the date column repeats only on the first row of each block and subsequent rows use a single dash '-' to in...
Write one SQL for exam scores aggregation
You are given an exam database. Write a single SQL statement (CTEs allowed; one final statement only) that satisfies all three requirements below. You...
Compute paid subscriber YoY counts by month
Write a single SQL query (PostgreSQL) that returns calendar-month counts of new paid subscribers starting from 2019-06-01 (inclusive) through the late...
Solve multi-part SQL with sliding windows
Assume 'today' is 2025-09-01. You are given the following tables. users(user_id INT PRIMARY KEY, signup_date DATE) orders(order_id INT PRIMARY KEY, us...
Solve SQL CTR and Python analytics tasks
Part A — SQL: Compute click-through rate (CTR) by pin_format for US new users. New users are those whose signup_date is within 30 days (inclusive) of ...
Design SQL cleaning, mapping, dedupe, and keying
Assume PostgreSQL 15. You may choose a different SQL dialect if you clearly state it and adapt syntax accordingly. Schema and small sample data: - Tab...
Solve advanced SQL for streaming analytics
You are given minute-level streaming telemetry. Each row in minute_streamed represents one minute during which a streamer was live; each row in minute...
Aggregate exam scores with NULL handling
Write a single SQL query (or CTE pipeline) to satisfy all requirements using the schema and sample data below. Replace any vendor-specific function wi...
Write SQL for recent customer activity
Write a single ANSI‑SQL query that produces, for every customer who has at least one non‑canceled order ever: (1) last_order_ts across all time consid...
Compute multi-account actives and unread coverage
You have two tables. Table: notifications +--------+------------+------------+-------------------+--------+ | userid | ds | time | notification_type |...
Compute violation rate and flag precision in SQL
You are analyzing a Trust & Safety product in BigQuery. Assume 'today' is 2025-09-01 (UTC). Define precise metrics and write SQL to compute them, bein...
Write SQL to flag coordinated fake accounts
Assume today is 2025-09-01. Schema and tiny samples: users(user_id, created_at, country) 1 | 2025-07-01 | US 2 | 2025-08-10 | IN 3 | 2025-08-15 | US 4...
Exclude free subscribers via anti-join
Extend your previous monthly new-subscriber + YoY query to exclude companies that ever received a free subscription, using an anti-join against Free_S...
Compute monthly new subscribers and YoY deltas
Write a single SQL query that returns monthly counts of new subscribers starting at 2019-06, plus year-over-year (same-month prior year) comparisons. ...
Design logical model and consumption
Design a logical data model and consumption layer supporting business and technical services architecture. Provide an ERD‑level description for Accoun...
Map sources to functional dataset with SQL
You must produce a functional, consumption‑ready dataset for daily exposure monitoring. Assume “today” = 2025‑09‑01. Use the last 7 calendar days by t...
Write SQL for streaming cohort metrics
Given the schema and sample data below, write SQL to answer the three tasks. Use standard SQL (window functions allowed). Assume timestamps are UTC. T...
Query email logs for deliverability insights
Using the schema and sample data below, write SQL to answer parts a–c. Assume timestamps are UTC. Today is 2025-09-01. Schema: - Emails(sent_id INT, m...