Topicwise Practice
Pick a topic, solve problems in order. Each path is curated from basic to advanced so you build real depth, not just breadth.
SQL for Absolute Beginners
Write your very first SQL queries with confidence. Every problem here teaches one keyword — SELECT, WHERE, ORDER BY, LIKE, IN, LIMIT, GROUP BY. No joins, no subqueries, just pure SQL fundamentals.
Joins & GROUP BY Mastery
The two most-tested SQL concepts in every DE interview. Master every join type and every aggregation pattern — from simple counts to multi-table funnel analysis.
SQL Window Functions Mastery
Go from basic aggregations to advanced analytical queries. Window functions are asked in almost every DE interview — master them here.
Python DSA — Beginner
Start from zero confidence and build it up. Every problem here uses one simple idea — a loop, a list, a dictionary, or a set. No tricks, just fundamentals that stick.
Python DSA — Intermediate
Step up to real interview problems. Arrays get trickier, you meet hash maps properly, and you start working with linked lists. Each problem introduces one new idea.
Python DSA — Senior Level
Hard patterns that separate senior engineers in FAANG and product company interviews. Two pointers, sliding window, recursion, stacks, queues, binary search, and dynamic programming.
PySpark Syntax Revision
A quick-reference practice path covering one problem per core PySpark operation. Run through this the day before an interview to refresh your API muscle memory.
PySpark for Data Engineers
Real DE pipeline problems from ingestion to analytics — joins, aggregations, window functions, sessionization, and retention. Solvable in PySpark, SQL, or Pandas.
Pandas Data Wrangling
The essential Pandas skills for DE and analytics engineering interviews — filtering, grouping, merging, pivoting, time-series, and window functions.