jbvc/database-design
Database design principles and decision-making. Schema design, indexing strategy, ORM selection, serverless databases.
62
Quality
62%
Does it follow best practices?
Impact
Pending
No eval scenarios have been run
Securityby
Passed
No known issues
optimization.md
Query Optimization
N+1 problem, EXPLAIN ANALYZE, optimization priorities.
N+1 Problem
What is N+1?
├── 1 query to get parent records
├── N queries to get related records
└── Very slow!
Solutions:
├── JOIN → Single query with all data
├── Eager loading → ORM handles JOIN
├── DataLoader → Batch and cache (GraphQL)
└── Subquery → Fetch related in one queryQuery Analysis Mindset
Before optimizing:
├── EXPLAIN ANALYZE the query
├── Look for Seq Scan (full table scan)
├── Check actual vs estimated rows
└── Identify missing indexesOptimization Priorities
- Add missing indexes (most common issue)
- Select only needed columns (not SELECT *)
- Use proper JOINs (avoid subqueries when possible)
- Limit early (pagination at database level)
- Cache (when appropriate)