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Data Systems⚪New

🌳 The Three-Legged Stool

Evaluate a system's architecture based on the trade-offs between Reliability, Scalability, and Maintainability.

⬇️ Foundation

💡 The Analogy

The Three-Legged Stool (Reliability, Scalability, Maintainability)

🧩 Consists of (The Parts)

Reliability (Fault Tolerance)

Continuing to work correctly even when things go wrong (Faults).

Scalability

The system's ability to cope with increased load without performance degradation.

Maintainability

The ease with which different people can work on the system over time (Operability, Simplicity, Evolvability).

Encoding & Evolution

Translating in-memory data structures into bytes for storage or transmission, handling backward/forward compatibility.

Data Models (SQL vs NoSQL)

The interface layer. How data is structured (Relational, Document, Graph) vs. how it is stored.

Query Languages (Declarative vs Imperative)

How we ask for data. Imperative tells the computer *how* to do it (loops); Declarative tells it *what* we want (SQL).

🔓 Unlocks Next

The Storage Black Box

Choose the right underlying storage engine (LSM vs B-Tree) for a specific workload.

🎯 Mastery Criteria

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🤔 Reflection:
"Pick a popular app (e.g., Twitter). Identify a feature that prioritizes Scalability over Consistency, and one that prioritizes Reliability over Latency."