Query Optimization in MongoDB
From the MongoDB cheat sheet · Indexes & Performance · verified Jul 2026
Query Optimization
Analyze and optimize query performance
javascript
// Explain query execution
db.users.find({
age: { $gte: 18 }
}).explain("executionStats")
// Check index usage
db.users.find({ email: "john@example.com" })
.hint({ email: 1 }) // Force specific index
.explain()
// Get index statistics
db.users.getIndexes()
db.users.totalIndexSize()💡 explain() shows query execution plan
📌 "COLLSCAN" means no index used (slow)
⚡ Profiler helps find slow queries
⚠️ hint() forces index but use carefully
🔗 Related: MongoDB Compass for visual analysis
performanceoptimization