Data Engineer Coding & Algorithms Interview Questions
Practice 53 real Coding & Algorithms interview questions for Data Engineer roles. From companies including Meta, Bytedance, Point72, Stripe, Amazon.
"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."
Implement Game Metadata Lookups
You are given a list of game metadata records. Build an in-memory representation that can store each game's name, release date, platforms, genre, publ...
Write SQL using joins and window functions
SQL Coding: Rank within Groups with Joins You are given two tables: accounts - account_id (string) - customer_id (string) - segment (string) — e.g., "...
Write SQL for first share and closest collaborator
You are given event data about users viewing design files. Assume the following tables: - files(file_id, creator_id) - creator_id is a VARCHAR user ...
Connect Points With Minimum Total Distance
You are given an array points, where points[i] = [xi, yi] represents a point on a 2D plane. The cost to connect two points i and j is their Manhattan ...
Build a Least-Recently-Used Store
Implement an in-memory key-value store with least-recently-used eviction. The store is initialized with a positive integer capacity and supports two o...
Validate an IPv4 address string
Given a string s, determine whether it is a valid IPv4 address. A valid IPv4 address: - Has exactly 4 parts separated by dots (.): x1.x2.x3.x4 - Each ...
Solve SQL and PySpark Data Tasks
Complete the following two data engineering coding tasks. Part A: Detect repeated crypto-transfer patterns in PostgreSQL You are given a PostgreSQL ta...
Write SQL revenue and anomaly queries
You are given two tables. Table: transactions | Column | Type | Description | |---|---|---| | transaction_id | int | Unique identifier for each transa...
Write SQL for app metrics
You are given a simplified schema for a photo-sharing app: - users(user_id, user_name, joined_at) - photos(photo_id, user_id, created_at) - follows(fo...
Compute Minimum Production Days
Question You are given a list of product IDs products, where products[i] is the type of the product that must be produced at step i, and a non-negativ...
Solve two string problems
You are asked to solve the following two coding problems. 1. Count unique Morse code translations You are given an array of lowercase English w...
Write SQL Data Transformation Queries
Use SQL to solve the following data transformation tasks. Assume standard SQL features are available, including window functions and recursive common ...
Compute Graph Spread and Portfolio Trades
Answer both implementation tasks. Task 1: Maximum connected-component label difference Implement maximumDifference(int gNodes, List<Integer> gFrom, Li...
Encode and Rebuild a Binary Tree
Design two functions for a binary tree: - encode(root) -> string - decode(data) -> root Each tree node contains an integer value and has up to two chi...
Write queries for follows and bookings
You are given tables/logs from a consumer app. Solve the following independent tasks. Part A — Active following as of a date (SQL) You have a follow e...
Write SQL for basic user metrics
You are given a simplified schema for a fictional social app called Nextagram: - users(user_id PK, username, created_at TIMESTAMP) - follows(follower_...
Write Transaction Analytics SQL Queries
You are given a credit-card transaction dataset with the following tables. transactions | column | type | description | |---|---|---| | transaction_id...
Implement a DAG task graph
Implement a class TaskGraph to represent a directed acyclic graph of tasks. Support these operations: 1. add_task(task_id: str) -> None: Add a task if...
Implement Election Report and Banking Pipeline
You are given two independent data engineering coding tasks. Task 1: SQL Election Exit Poll by State Report An election analytics team needs a report ...
Implement two string utility functions
Implement the following Python functions: 1. number_of_character(string, char) - Return the number of times character char appears in string. - ...