Memory Sheet

Concepts

Theory
- CAP Theorem
Evaluation dimensions
- Scalability
  - Concept
  - Type of scaling
    - Concepts
    - Cons
  - How to achieve high scalability
- Availability
  - Concept
  - How to achieve high availability
  - Metrics
- Consistency
  - Models
- Performance
  - Metrics
API
- API architectural styles
  - SOAP, REST, gRPC, GraphQL, WebSocket, Webhook.
  - Concept, pros, cons, use cases.
- API design
  - REST API design best practices.

Components

Database

Types
- Main types
- Subtypes for NoSQL
- Concepts, pros, cons, use case, examples.
- Factors for choosing database.
Index
- Main categories
- Types
- Best practices
Techniques
- Replication
  - Types
- Partitioning
  - Types
  - Common issues and solutions
    - Join operation
    - Hot spot
  - Split data into multiple databases or multiple tables?
- Sharding
  - Types
  - How to query
    - On sharding key
    - On non-sharding columns (3 solutions)
Design
- Schema design
  - Steps
  - Normalization
    - 1NF, 2NF, 3NF
  - Denormalization

Message queue

Basics
- Pros and cons
- Selections
  - Factors
  - Differences and use cases between RabbitMQ and Kafka
- Common problems and solutions
  - How to guarantee message order? (1 solution)
  - How to handle duplicated message? (2 solutions)
- Use cases (5)
Kafka
- Terminologies
  - Topic, partitions, consumer groups
- Patitions
  - Concepts, relationship between partions and consumer group.
- Why Kafka fast?