Databases10 lessons15 quiz questions
NoSQL Databases
Master NoSQL databases for software engineering interviews — covering MongoDB, Redis, DynamoDB, data modeling, and when to choose NoSQL over SQL.
What You Will Learn
- ✓NoSQL Fundamentals — Types, CAP Theorem, BASE
- ✓MongoDB CRUD — insertOne, find, updateOne, deleteOne
- ✓MongoDB Aggregation Pipeline — $match, $group, $sort, $project
- ✓MongoDB Indexing & Performance — Compound, Text, explain()
- ✓Redis Data Structures — String, Hash, List, Set, Sorted Set
- ✓Redis Caching Patterns — Cache-aside, Write-through, TTL
- ✓DynamoDB — Partition Keys, GSI, LSI, Capacity Modes
- ✓NoSQL Data Modeling — Embedding vs Referencing, Denormalization
- ✓NoSQL vs SQL — Trade-offs, When to Use Which
- ✓Interview Patterns & Common NoSQL Questions
Overview
Master NoSQL databases for software engineering interviews — covering MongoDB, Redis, DynamoDB, data modeling, and when to choose NoSQL over SQL.
NoSQL Fundamentals
4 Types: Document (MongoDB — JSON docs), Key-Value (Redis — hash map), Wide-Column (Cassandra — rows+columns), Graph (Neo4j — nodes+edges).
CAP Theorem: A distributed system can guarantee only 2 of 3: Consistency, Availability, Partition Tolerance. MongoDB: CP. Cassandra: AP. Redis: CP.
BASE vs ACID: Basically Available, Soft state, Eventually consistent. NoSQL trades strict ACID for scalability.
When NoSQL: Flexible/changing schema, horizontal scaling, high write throughput, unstructured data.
CAP Theorem Diagram
Java Implementation
Python Implementation
Sample Quiz Questions
1. Which NoSQL database type is best suited for storing a social network graph where you need to traverse friend-of-friend relationships?
Application·Difficulty: 2/5
2. In the CAP theorem, which two properties does MongoDB prioritize?
Knowledge·Difficulty: 2/5
3. What is the correct order of stages in a MongoDB aggregation pipeline to optimize performance?
Application·Difficulty: 3/5
+ 12 more questions available in the full app.
Related Topics
Master NoSQL Databases for Your Next Interview
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