Index Basics
Index, EK, SPECIAL, DATA, STRUCTURE, hai (B-tree) JO, EK, FIELD, ke, VALUES, ko, EFFICIENTLY, SEARCHABLE, ORDER, mein, STORE, karta hai — createIndex(), EK, NAYA, INDEX, banaта hai.
Indexes, WITHOUT, unke, QUERIES, KAAFI, SLOW, HOTI, HAIN — "COLLECTION, SCAN" (HAR, SINGLE, DOCUMENT, CHECK, karna) badi, COLLECTIONS, PAR, EXTREMELY, EXPENSIVE, hai.
// Index banaна:
db.users.createIndex({ email: 1 }); // 1 = ascending order
// Ab, ye, query, FAST, hai (index, use, hota, hai):
db.users.find({ email: "aarav@example.com" });
// Indexes, list, karna:
db.users.getIndexes();- Index = B-tree data structure, field values, ko, efficiently, searchable, banata, hai
- Indexes ke bina, queries, "collection scan" karti, hain — SLOW
- _id, PAR, DEFAULT, index, HAMESHA, exist, karta, hai
HAR, index, EXTRA, disk, space, aur, memory, consume, karta hai — aur, HAR, write, operation, (insert/update/delete) ko, index, ko, bhi, UPDATE, karna, PADТA, hai. Bahut, saare, unnecessary, indexes, write, performance, ko, HURT, kar, sakte, hain.
$indexStats, aggregation, stage, se, HAR, index, ka, USAGE, COUNT, dekha, ja, sakta hai — agar, EK, index, KABHI, use, nahi, ho, raha, USE, drop, karna, chahiye, write, performance, improve, karne, ke, liye.
db.users.aggregate([{ $indexStats: {} }]);
db.users.dropIndex("unused_field_1");