Data Engineering Fundamentals

Here's the fundamental Data Engineering stack you need to master, no matter the company you're aiming for.


Layer 1: Data Modeling & Schema Design


The foundation everything builds on.


- Normalization vs denormalization tradeoffs.

- Star and snowflake schemas.

- Slowly changing dimensions.

- Partitioning and bucketing strategies.


Poor modeling? Your queries will never scale.


Layer 2: SQL & Query Optimization


Your primary language for data.


- Complex joins and window functions.

- Query execution plans and indexes.

- Subquery vs CTE performance.

- Aggregation optimization techniques.


Can't write efficient SQL? You won't pass the technical.


Layer 3: Distributed Systems Fundamentals


How data systems actually work at scale.


- CAP theorem and consistency models.

- Partitioning and replication strategies.

- Distributed query processing.

- Fault tolerance and recovery.


Miss these concepts? You can't reason about production issues.


Layer 4: Data Pipeline Architecture


Moving data reliably at scale.


- Batch vs streaming tradeoffs.

- Idempotency and exactly-once processing.

- Backfill strategies and data quality.

- Orchestration and dependency management.


Bad pipelines? Data teams lose trust in your work.


Layer 5: Storage Systems & Formats


Where and how you store matters.


- Row vs columnar storage tradeoffs.

- Parquet, ORC, Avro characteristics.

- Data lake vs warehouse patterns.

- Compression and encoding strategies.


Wrong storage choices kill query performance.


Layer 6: Data Quality & Observability


Production data is messy.


- Schema validation and evolution.

- Data lineage and impact analysis.

- Monitoring pipeline health.

- SLA definition and alerting.


No observability? You're flying blind in production.


Layer 7: Performance & Scalability


The difference between junior and senior.


- Understanding data skew and hotspots.

- Memory vs disk tradeoffs.

- Caching strategies and materialization.

- Cost optimization techniques.

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