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16 data career roadmaps with curated resources from zero to job-ready

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1,625 coding problems in Python & SQL with real company-style datasets

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Quick Recall

496 interview recall cards and interactive SQL exercises for rapid prep

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1,625 problems on real industry datasets — graded in your browser in milliseconds. No backend, no waiting.

15 Industry Datasets·4 Difficulty Levels·Instant Feedback

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query.sql ACCEPTED

SELECT

c.campaign_name,

SUM(i.cost) AS total_spend,

COUNT(DISTINCT cl.click_id) AS clicks

FROM campaigns c

JOIN impressions i ON c.id = i.campaign_id

LEFT JOIN clicks cl ON i.id = cl.impression_id

WHERE c.status = 'active'

GROUP BY c.campaign_name

ORDER BY total_spend DESC;

3 rows · 6ms

campaign_name	total_spend	clicks
Holiday Push	42,850	1,247
Brand Awareness	38,200	982
Retarget Q4	25,600	654

solve.py ACCEPTED

import pandas as pd

import numpy as np

def solve(campaigns, impressions, clicks):

active = campaigns[campaigns['status'] == 'active']

df = (active

.merge(impressions, on='campaign_id')

.merge(clicks, on='impression_id', how='left'))

return (df

.groupby('campaign_name')

.agg(total_spend=('cost','sum'), clicks=('click_id','nunique'))

.sort_values('total_spend', ascending=False)

.reset_index())

3 rows · 42ms

campaign_name	total_spend	clicks
Holiday Push	42,850	1,247
Brand Awareness	38,200	982
Retarget Q4	25,600	654

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Recall

Sharpen Your Knowledge, Fast

Two ways to drill interview-critical concepts: swipe-based recall cards across 5 categories, and hands-on SQL exercises with a live editor.

Interview Recall Cards

496 cards · 5 categories · Swipe to master

Start

SQL

96 cards

JoinsWindow FnsCTEsAggregations

Python & Pandas

111 cards

OOPDataFramesNumPyFile I/O

Statistics

83 cards

HypothesisBayesianA/B TestsProbability

Machine Learning

117 cards

Deep LearningFeature EngMLOpsEvaluation

LLMs & GenAI

89 cards

RAGFine-tuningAgentsPrompting

SQL Exercises

33 lessons · 71 exercises · Live SQL editor

Start

Foundations

SELECT, WHERE, ORDER BY

Joins

INNER, LEFT, Self Joins

Aggregations

GROUP BY, HAVING, COUNT

Window Fns

ROW_NUMBER, RANK, LAG

Date Fns, Time Periods

String & Sets

UNION, String Fns

Advanced

Top-N, Pivoting, Series

Optimization

Indexes, Anti-patterns

Learn

14 Interactive Courses: 7 Free, 7 Pro

Start with SQL, Python, pandas, and statistics, then move into LLM foundations, RAG systems, AI agents, AI evals, experimentation, and machine learning.

Showing 4 featured AI courses. Module 1 is free on every Pro course.

LLM Foundations

Free·8 modules · ~8h

Tokens, attention, transformer blocks, training, inference, post-training, and interpretability.

M1/8

TokensAttentionTransformersInterpretability

Building RAG Systems & Vector Search

Pro·8 modules · ~9h

BM25, embeddings, chunking, hybrid search, ANN indexes, reranking, grounding, and RAG evals.

M1/8

RAGEmbeddingsHybrid SearchReranking

Building AI Agents

Pro·8 modules · ~9h

Agent loops, tools, planning, reflection, memory, multi-agent systems, evaluation, and guardrails.

M1/8

AgentsTool UsePlanningGuardrails

AI Evals: Test, Measure & Ship LLM Apps

Pro·8 modules · ~9h

Error analysis, scorers, LLM-as-judge, confidence intervals, regression gates, and production evals.

M1/8

EvalsScorersLLM JudgeCI Gates

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Career Paths

Your Roadmap to a Data Career

16 structured paths — curated resources, regional market notes, official docs, and LDS practice problems in the exact dependency order.

Best entry point

Data Analyst

Extract insights, build dashboards, and turn business questions into SQL, Python, and visualization workflows.

SQLPythonStatisticsDashboards

8 stages · 6-12 monthsView Roadmap

Most versatile

Data Scientist

Use statistics, machine learning, experimentation, and product judgment to turn messy data into decisions.

PythonStatisticsMachine learningExperimentation

8 stages · 9-14 monthsView Roadmap

Builds production ML

Machine Learning Engineer

Build, deploy, optimize, and maintain machine learning systems that serve real users.

PyTorchMLOpsModel servingSystems

8 stages · 9-13 monthsView Roadmap

Data infrastructure

Data Engineer

Design pipelines, warehouses, lakehouses, and streaming systems that make data reliable.

8 stages · 10-14 monthsView Roadmap

LLM product builder

AI Engineer

Ship LLM applications, RAG systems, agents, evals, and production AI features.

LLM APIsRAGAgentsEvals

8 stages · 6-12 monthsView Roadmap

Trust layer

Analytics Engineer

Turn raw warehouse data into governed models, metrics, tests, and trusted analytics surfaces.

dbtSQLWarehousesMetrics

7 stages · 8-12 monthsView Roadmap

Production ML ops

MLOps Engineer

Keep ML systems alive with CI/CD, model serving, monitoring, feature stores, and production operations.

DockerKubernetesMLflowMonitoring

8 stages · 10-14 monthsView Roadmap

Customer AI deployment

Forward Deployed AI Engineer

Embed with customers, scope valuable AI workflows, build production systems, and prove adoption with evals.

LLM appsCustomer discoveryEvalsFull-stack

8 stages · 6-12 monthsView Roadmap

Dashboard and KPI owner

Business Intelligence Analyst

Build trusted reporting, dashboards, KPI systems, and business intelligence workflows.

SQLDashboardsKPIsStakeholders

7 stages · 4-8 monthsView Roadmap

Funnels and experiments

Product and Growth Analyst

Analyze funnels, experiments, retention, pricing, and product behavior to improve user outcomes.

SQLA/B testingFunnelsRetention

7 stages · 6-10 monthsView Roadmap

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Curated AI news scored by relevance, plus deep-dive articles — updated daily.

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6.8Google Dialogflow Flaw Exposes Chatbot Hijack Risk27m ago 6.1Mumbai Leads as Tier-2 Cities Catch Up in AI Hiring27m ago 6.9Alberta Releases Open-Source AI Playbook for Government35m ago 6.8Chatbots Disseminate Beijing's Talking Points Abroad38m ago 5.8Platforms Adopt Automated Moderation as Default42m ago

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News5 min read

15 Industry Domains

Practice on data modeled after real companies.

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Career Paths

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Quick Recall

Write SQL & Python. Get Graded Instantly.

See Your Code Come to Life

Sharpen Your Knowledge, Fast

Interview Recall Cards

SQL Exercises

14 Interactive Courses: 7 Free, 7 Pro

LLM Foundations

Building RAG Systems & Vector Search

Building AI Agents

AI Evals: Test, Measure & Ship LLM Apps

Your Roadmap to a Data Career

Data Analyst

Data Scientist

Machine Learning Engineer

Data Engineer

AI Engineer

Analytics Engineer

MLOps Engineer

Forward Deployed AI Engineer

Business Intelligence Analyst

Product and Growth Analyst

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From the Blog

Ford Bet on AI to Catch Defects. Then It Rehired 350 Human Engineers.

Every Investor Passed on Etched in 2023. It Just Booked $1 Billion in Orders.

Anthropic Made Three Promises. Washington Gave Back Fable 5 and Mythos 5.

15 Industry Domains

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