Database
Overview
Database systems provide structured data storage, retrieval, and management for applications and services.
They are critical for maintaining data integrity, performance, and long-term reliability.
🎯 Scope
- SQL and NoSQL systems
- Performance and query efficiency
- Backup and recovery strategies
🧠 Key Concepts
- Databases must balance performance, reliability, and scalability
- Structured (SQL) vs flexible (NoSQL) models serve different use cases
- Indexing and query design directly impact performance
- Backup and recovery must be tested, not assumed
System Architecture
Data Models
- SQL (relational, structured schema)
- NoSQL (flexible, document/key-value models)
- Choose based on application requirements
Performance
- Query optimization and indexing
- Avoid unnecessary joins or heavy queries
- Monitor load and response times
Backups
- Regular automated backups
- Offsite or cloud backup strategy
- Verify restore process works
⚠️ Common Mistakes
- No backup validation
- Poor indexing leading to slow performance
- Overcomplicating schema design
- Mixing SQL/NoSQL without clear purpose
- Ignoring storage growth
📊 Related Systems
✅ Result
A reliable database system that supports performance, data integrity, and long-term system stability.