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The notes we actually revise from before interviews.
Spark, SQL, Kafka, Snowflake, Airflow, dbt, warehousing and system design, written as revision notes, not textbooks.
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- PDF notes
- 117
- pages of revision
- 2,839
- topics covered
- 21
New · the complete notes · sold separately from the vault
The complete notes, in one book
Twenty-eight chapters, Hadoop to Terraform, in one 157-page PDF. Sold on its own: the vault and the Learn Pass do not include it.
Data Engineering End to End Notes
What the 28 chapters give you:
- 28 chapters with commands, configs and interview questions
- Free for Data Engineering cohort learners and mentorship members
- 20 pages free to read after a Google sign-in
₹499 · PDF · 20 pages free to read
New · data modelling from zero to hero · sold separately from the vault
Data modelling, from a paper register to sharded systems
Twenty chapters in seven parts, ER diagrams to replication, then six case studies, in one 93-page PDF. Sold on its own: the vault and the Learn Pass do not include it.
Data Modelling: Zero to Hero
What the 20 chapters give you:
- 20 chapters with worked examples, 6 case studies and interview questions
- Free for Data Engineering cohort learners and mentorship members
- 20 pages free to read after a Google sign-in
₹299 · PDF · 20 pages free to read
Just launched · sold separately from the vault
Experienced Data Engineering Interview Kit 2026
The 11 decks:
- 01 SQL and modeling
- 02 Python coding
- 03 PySpark
- 04 Kafka and streaming
- 05 AWS, Azure and GCP
- 06 Databricks and Snowflake
- 07 Airflow, dbt and DataOps
- 08 System design
- 09 Scenario questions
- 10 Trade-offs
- 11 Behavioural and offer
₹499 · PDF · 20 pages free to read
New · for data analyst interviews · sold separately from the vault
Data Analytics Interview Kit 2026
The 11 decks:
- 01 SQL
- 02 Business SQL
- 03 Excel
- 04 Python and pandas
- 05 Statistics
- 06 A/B testing
- 07 Product sense
- 08 Power BI and Tableau
- 09 Cases and guesstimates
- 10 Take-home and storytelling
- 11 Behavioural and offer
₹499 · PDF · 20 pages free to read
New book · sold separately from the vault
Data Engineering System Design: Zero to Hero
- 100 reported questions from 30+ companies, each tagged by evidence
- The PIPELINE method: eight steps for the 45 minutes
- 26 designs worked end to end, 19 cheat sheets and a master checklist
₹499. PDF, 111 pages.
Just added
Latest notes
Just added — newest first.
NewSQL100 SQL Interview Questions for Product-Based Companies
100 questions from easy to expert for product-based company interviews, each solved on one store dataset with the PostgreSQL 16 query and its real output.
217 pages3.0 MB
Big DataApache Spark & PySpark — End to End Notes
Spark's engine, execution model and optimiser, then PySpark hands-on from RDDs to streaming. Chapters 6 and 7 of the Data Engineering End to End Notes.
14 pages537 KB
StreamingApache Kafka — End to End Notes
Topics, partitions, brokers, replication, producers, consumers, Schema Registry and real setups. Chapter 10 of the Data Engineering End to End Notes.
7 pages456 KB
OrchestrationApache Airflow — End to End Notes
DAGs, operators, XCom, TaskFlow, scheduling, catchup and backfill, connections and alerts. Chapter 11 of the Data Engineering End to End Notes.
7 pages464 KB
The library
117 PDF notes · first download free
- NewSQL
100 SQL Interview Questions for Product-Based Companies
100 questions from easy to expert for product-based company interviews, each solved on one store dataset with the PostgreSQL 16 query and its real output.
217 pages3.0 MB
- Big Data
Apache Spark & PySpark — End to End Notes
Spark's engine, execution model and optimiser, then PySpark hands-on from RDDs to streaming. Chapters 6 and 7 of the Data Engineering End to End Notes.
14 pages537 KB
- Streaming
Apache Kafka — End to End Notes
Topics, partitions, brokers, replication, producers, consumers, Schema Registry and real setups. Chapter 10 of the Data Engineering End to End Notes.
7 pages456 KB
- Orchestration
Apache Airflow — End to End Notes
DAGs, operators, XCom, TaskFlow, scheduling, catchup and backfill, connections and alerts. Chapter 11 of the Data Engineering End to End Notes.
7 pages464 KB
CloudMicrosoft Azure — End to End Notes
Identity, compute, storage, networking, databases, DevOps and monitoring on Azure. Chapter 16 of the Data Engineering End to End Notes.
8 pages459 KB
CloudGoogle Cloud Platform — End to End Notes
IAM, compute, storage, databases, networking, Vertex AI, operations and cost control. Chapter 17 of the Data Engineering End to End Notes.
7 pages449 KB
WarehouseData Warehousing — End to End Notes
OLTP vs OLAP, warehouse architecture, dimensional modelling, lakes and lakehouses, and performance. Chapter 20 of the Data Engineering End to End Notes.
5 pages426 KB
Big DataBig Data & Hadoop — End to End Notes
Why one machine stops being enough, Hadoop and HDFS inside out, MapReduce and YARN. Chapters 1 to 3 of the Data Engineering End to End Notes.
16 pages293 KB
Big DataApache Hive — End to End Notes
SQL on big data: architecture, setup, tables, partitions, buckets, functions and joins. Chapter 4 of the Data Engineering End to End Notes.
7 pages203 KB
Big DataApache HBase — End to End Notes
NoSQL on Hadoop: random, real-time reads and writes on top of HDFS. Chapter 5 of the Data Engineering End to End Notes.
6 pages166 KB
PipelinesData Pipelines — End to End Notes
Pipeline anatomy, ETL vs ELT, batch vs real-time, windows and the Lambda architecture. Chapter 8 of the Data Engineering End to End Notes.
6 pages150 KB
CloudDocker & Compose — End to End Notes
Images, containers, Dockerfiles, debugging and multi-container stacks with Compose. Chapter 9 of the Data Engineering End to End Notes.
6 pages164 KB
CloudAWS for Data Engineers — End to End Notes
IAM and EC2, S3 and Route 53, Lambda and VPC, Glue and Athena with the Data Catalog. Chapters 12 to 15 of the Data Engineering End to End Notes.
19 pages307 KB
ArchitectureDistributed Databases & Cassandra — End to End Notes
CAP, consistency, replication vs sharding; Cassandra's masterless design, modelling and CQL. Chapters 18 and 19 of the Data Engineering End to End Notes.
12 pages222 KB
WarehouseAmazon Redshift — End to End Notes
MPP columnar warehouse on AWS: architecture, loading, table design, tuning, Spectrum and querying. Chapter 21 of the Data Engineering End to End Notes.
7 pages169 KB
WarehouseGoogle BigQuery — End to End Notes
Serverless warehouse: Dremel, datasets and tables, loading, partitioning, clustering and SQL. Chapter 22 of the Data Engineering End to End Notes.
6 pages163 KB
CloudKubernetes — End to End Notes
Architecture, GKE, core objects, storage, autoscaling and stateful data workloads. Chapter 23 of the Data Engineering End to End Notes.
7 pages186 KB
WarehouseSnowflake — End to End Notes
Architecture, objects and RBAC, Time Travel, warehouses, stages, Snowpipe, Streams and Tasks. Chapter 24 of the Data Engineering End to End Notes.
8 pages195 KB
GitLab & CI/CDGitLab CI/CD — End to End Notes
The DevSecOps platform, runners and .gitlab-ci.yml from the first job to scheduled pipelines. Chapter 25 of the Data Engineering End to End Notes.
8 pages190 KB
CloudTerraform — End to End Notes
Infrastructure as Code: core workflow, state, modules, variables, expressions and real AWS builds. Chapter 26 of the Data Engineering End to End Notes.
8 pages193 KB
Big DataDatabricks SQL & Performance Notes
All 19 topics for making Databricks and Spark queries fast: warehouses and Photon, Query Profile and EXPLAIN, joins, AQE, skew, pruning, stats and caching.
25 pages432 KB
ArchitectureDelta Lake — Complete Notes
The log, ACID and OCC, time travel, VACUUM, OPTIMIZE, ZORDER, liquid clustering, MERGE, CDF and deletion vectors. Every block ran on a real Delta table.
27 pages518 KB
AnalyticsWhy Did the Metric Drop? — One Framework, 13 Worked Cases
The 6-step framework interviewers grade, metric trees with worked arithmetic, Simpson's paradox with real numbers, 13 cases from food delivery to UPI.
19 pages1.7 MB
BI & VizPower BI — End to End Project
Raw CSVs to a published, secured report: a real brief with 8 questions, every M and DAX formula written out, an April to March fiscal year, RLS, refresh.
19 pages1.7 MB
CloudWhy Your Data Bill Doubled — Cloud Cost Optimisation
How Snowflake, Databricks, BigQuery and AWS actually bill, the queries that find the expensive 10%, hidden network costs, a worked case and FinOps habits.
19 pages1.7 MB
AI & LLMsData Engineering for AI — RAG, Agents & LLM Pipelines
The pipelines behind RAG, agents and LLM apps: parsing, six chunking strategies, versioned embeddings, pgvector hybrid search, fresh indexes, evals, ACLs.
19 pages1.8 MB
Data QualityThe 2 AM Pager — 25 Data Pipeline Incidents
25 data pipeline incidents on Spark, Airflow, Kafka, CDC, warehouses and S3: symptom, first 10 minutes, root cause, fix, prevention, reruns, postmortems.
19 pages1.8 MB
AnalyticsSQL vs Pandas vs Excel — 18 Problems, Solved Three Ways
The same 18 business questions answered in SQL, pandas and Excel side by side on one dataset. SQL ran on DuckDB, pandas on 3.0, and the results match.
18 pages357 KB
AnalyticsCohorts, Funnels & Retention — Product Analytics in SQL
DAU/MAU, ordered funnels, sessions, the retention triangle, four retention definitions, LTV, growth accounting and RFM, as SQL that runs on real data.
22 pages396 KB
CloudDocker & Kubernetes for Data Engineers
Package a PySpark job, run a local stack with Compose, then schedule it with CronJobs, the Spark Operator and Airflow 3 on Kubernetes, laptop to cluster.
25 pages439 KB
StreamingCDC — End to End Notes
How a database change becomes a correct row in your lake: write-ahead logs, Debezium, Kafka, ordering, deletes, MERGE, SCD 2 and the 2 AM failures, in SQL.
25 pages455 KB
ArchitectureIceberg vs Delta vs Hudi — Open Table Formats
Why a folder of Parquet is not a table, and how Iceberg, Delta and Hudi fix it. Snapshots, logs and deletes run for real on PyIceberg and delta-rs.
26 pages510 KB
PythonPython for Data Engineering — End to End Notes
From installing Python to DSA, Big-O and the coding patterns DE interviews keep reusing, with a 10-week plan to get there. Every topic comes with the approach, code that runs, and the real output.
80 pages477 KB
SQLSQL — End to End Notes
From your first SELECT to the patterns interviewers keep reusing. Every topic comes with the approach to solve it, a query that runs, and the real output.
40 pages329 KB
Fundamentals PopularData Engineering: From Zero to Production & Interview Ready
Lecture Zero plus fourteen chapters — Linux, SQL, Python, data modeling, storage, cloud, pipelines, Spark, Airflow, Kafka, data quality, a portfolio project and the interview loop. Every figure measured. Free, and it never uses your free note.
244 pages1.4 MB
GitLab & CI/CD PopularGitLab for Data Engineers — Complete Notes
Twenty pages on how your code actually reaches production: Git and merge requests, .gitlab-ci.yml line by line, rules and runners, dbt Slim CI without dbt Cloud, shipping Airflow DAGs and Databricks asset bundles, plus 25 rapid-fire interview questions.
20 pages1.6 MB
PySpark PopularPySpark on Cricket Data — Complete Notes
The full written notes from the 29 August live build: loading raw IPL match data into Databricks, DataFrame analysis with groupBy, window functions, joins and UDFs, tuning with caching and partitioning, and writing the processed outputs to Delta.
20 pages1.8 MB
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SQL, Python, Power BI, PySpark and Excel — full video lessons with MCQs and a proctored skill test at the end. The notes are the summary; this is the teaching.
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23 deep-dive modules, 74 sessions
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