Software Engineer Data Manipulation (SQL/Python) Interview Questions
Practice 54 real Data Manipulation (SQL/Python) interview questions for Software Engineer roles. From companies including Amazon, DoorDash, NVIDIA, Akuna Capital, Instacart.
"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."
Design payment-to-invoice matcher with priorities
Design and implement a payment-to-invoice matcher. Inputs: (a) invoices, a list like ["invoice-id-1, 10000, 2022-01-01", "invoice-id-2, 30000, 2022-01...
Implement Spring MVC to find top-enrolled course
Implement a Spring MVC service that returns the course with the highest number of enrolled students from a relational database pre-populated by provid...
Pivot transactions by date without date libs
Given a stream of transaction rows (shopper_id, date_str, amount) where date_str is ISO format 'YYYY-MM-DD', produce a pivoted report for a specified ...
Compute most popular location with weights
You are given a dataset of voting records for concert locations. Each record includes voter_id, location_text, and an optional numeric weight (default...
Compute dasher payout from API data
Given a REST endpoint GET /payout that returns each delivery’s components (base pay, distance/time bonuses, promotions, tips, fees, adjustments, taxes...
Generate user notifications from schedules
Given a schedule template format and user profile data (timezone, locale, delivery preferences), implement a program that generates a user notificatio...
Fill missing values with means
You are given a pandas DataFrame df with missing values in multiple numeric columns. Write a concise pandas expression to replace NaNs in each numeric...
Write complex SQL for cohorts and retention
Given tables users(uid, created_at, country), orders(order_id, uid, amount, created_at, status), and events(uid, ts, event_type, campaign), write one ...
Find users with multi-country successful logins
Given a table login_attempts with columns: user_id (TEXT), timestamp (TIMESTAMP), status (TEXT), and country (TEXT), write an SQL query to return the ...
Compute courier pay with peak-hour rules
Implement compute_pay(deliveries) to calculate a delivery driver's daily pay from a list of delivery records. Each record may include times, miles, ba...
Pivot data without date libraries
Transform a tall dataset into a wide, pivoted view without using any date/time libraries. Input: a list of records (date, store_id, metric, value) whe...
Count IoT devices matching date and threshold
Implement function numDevices(statusQuery, threshold, dateStr) that returns the number of IoT devices from a paginated REST API that were added in the...
Implement and debug event filtering in Python
You are given a list of event dictionaries with keys: id (str), type (str), ts (int, seconds since epoch), payload (dict). Implement filter_events(eve...
Implement 2D convolution using NumPy slicing
Implement 2D convolution on a 4×4 input and a 3×3 filter with stride 1 using NumPy. Avoid explicit Python loops by relying on array slicing, broadcast...
Calculate cost from orders with SQL
You have two tables: orders(order_id INT, user_id INT, order_date DATE, quantity INT, unit_price DECIMAL, coupon_code VARCHAR) and coupons(code VARCHA...
Write SQL to Join Merchants and Triple Restaurant Points
You are given: ( 1) a CSV file merchants.csv with columns: merchant_name, merchant_code, category; ( 2) a database table transactions(user_id INT, mer...
Parse CSV and format transactions
Given a CSV file containing many transactional records with columns Merchant, Amount, Date (YYYY-MM-DD), and Status, write a script to parse the file ...
Write PostgreSQL updates with date filters
Write PostgreSQL statements to: ( 1) update a flight's price and set updated_at correctly; ( 2) upsert a booking record with conflict handling; ( 3) s...
Find returning users from access logs
Given a large user access log, parse it and identify which user_ids are returning customers—i.e., they have at least one visit on two or more distinct...
Write SQL with window functions for analytics
Given a table events(user_id, event_time, event_type, value), write SQL to: a) compute each user's rolling 7-day sum of value by day, b) rank each use...