Most students can read a JOIN example in a textbook. Far fewer can write a multi-table query from scratch that returns the correct result on the first attempt. Placement tests don't ask "explain what GROUP BY does." They say: "Write a query."
Queries are graded by difficulty. Students progress through a structured path — each level builds on the SQL skills from the previous one.
130+ challenges
Simple SELECT, WHERE filtering, sorting, LIKE patterns, IN/BETWEEN, NULL handling, and basic aggregate functions. The fundamentals every student must master first.
150+ challenges
Multi-table JOINs, GROUP BY with HAVING, subqueries, aliases, and nested queries. This is where students go from "I can fetch data" to "I can combine and analyse data across tables."
120+ challenges
Window functions (RANK, ROW_NUMBER, LAG/LEAD), CTEs, correlated subqueries, CASE expressions, self-joins, and multi-level aggregations. The difficulty level tested by product companies and analytics roles.
100+ challenges
SQL challenges modeled on questions asked by Accenture, Capgemini, Cognizant, TCS, and product companies. Timed practice that simulates actual placement database rounds — format, constraints, and difficulty matched.
Each task type reflects a real-world database scenario — from simple lookups to multi-step analysis problems that mirror what companies test in placement rounds.
Write queries to fetch specific data from one or more tables. Filter, sort, paginate, and format results to match the expected output exactly.
Combine data across 2–4 related tables using INNER, LEFT, RIGHT, and FULL joins. Handle NULL values, duplicate rows, and table aliases correctly.
Group data, compute summaries, and filter aggregated results. Running totals, averages by category, percentile calculations, and conditional aggregation.
Use window functions to rank, number, and compare rows within partitions. Period-over-period comparisons, running sums, and nth-value lookups.
Create tables with proper constraints, define relationships, write ALTER statements, and design schemas. Tests structural SQL skills beyond just querying.
Each challenge shows a problem statement, the table schema (columns, types, relationships), and sample data. You know exactly what tables you're working with.
Write the complete SQL query from scratch in the editor. Syntax highlighting, auto-complete for table/column names, and multi-line editing. Choose MySQL, PostgreSQL, or T-SQL.
Hit "Run" — your query executes against a pre-loaded dataset with hundreds of rows. See the actual result set instantly. Run as many times as you need — unlimited executions.
Your result is compared against the expected output — row count, column values, and order. Exact match = pass. Stuck? AI hints guide your thinking without writing the query for you.
PChallenges are tagged by topic. Practice by difficulty, by topic, or both. Here's what the question bank covers:
Filtering, operators, patterns
COUNT, SUM, AVG, MIN, MAX
INNER, LEFT, RIGHT, FULL, SELF
Grouping, HAVING, ROLLUP
Scalar, correlated, EXISTS/IN
RANK, ROW_NUMBER, LAG/LEAD
WITH clause, recursive queries
UNION, INTERSECT, EXCEPT
CREATE, ALTER, constraints
INSERT, UPDATE, DELETE
Conditional logic in queries
DATEADD, DATEDIFF, formatting
CONCAT, SUBSTRING, REPLACE
PK, FK, UNIQUE, CHECK
TCS, Accenture, Capgemini style
Your queries run against actual database engines with pre-loaded, realistic datasets — not 5-row toy tables. The experience mirrors real placement SQL rounds.
Tables with hundreds of rows across multiple related tables — employees, departments, orders, products, customers. Realistic data, not "John, Jane, Jim."
See the table structure, column types, and relationships before writing your query. No guessing what columns exist or how tables connect.
Switch between MySQL, PostgreSQL, and T-SQL. Same problem, different syntax — practice the engine your target company uses.
Run, tweak, re-run. No daily limits. Iteration is how you learn SQL — we don't restrict it.
Your query output is compared row-by-row against the expected result. Exact match = pass. You know immediately if you're right.
Stuck on which JOIN type to use? Not sure about GROUP BY vs HAVING? The AI hints at the concept — never writes the query for you.
Track completion across Beginner, Intermediate, Advanced, and Company-Specific levels. See exactly where you stand.
What percentage of your queries return the correct result on the first run? The metric that shows real understanding.
How long you take vs. the benchmark. Placement SQL rounds are timed — speed matters alongside correctness.
Visual breakdown of strong vs. weak topics. JOINs mastered but window functions weak? The heatmap shows it immediately.
Earn progression badges: Query Rookie, Join Master, Window Wizard, SQL Ace. Visible on your practice profile.
Class-level SQL readiness metrics. See which students can handle JOINs and which still struggle with basic WHERE clauses.
E-305, Industrial Area, Sahibzada Ajit Singh Nagar, Punjab 160055, IN
