Mongoose Population
ref, option, schema, mein, SPECIFY, karta hai, ki, EK, field, KIS, model, ko, REFERENCE, karta hai — populate(), ISI, reference, ko, USE, karके, RELATED, document, ko, FETCH, karके, EMBED, kar, deta hai.
populate(), INTERNALLY, EK, SEPARATE, QUERY, RUN, karta hai — MULTIPLE, NESTED, populate() calls, PERFORMANCE, ko, AFFECT, kar, sakte, HAIN (SQL, ke, N+1, problem, jaisa).
const orderSchema = new mongoose.Schema({
customer: { type: mongoose.Schema.Types.ObjectId, ref: "User" },
items: [String]
});
const Order = mongoose.model("Order", orderSchema);
// populate() se, customer, ki, poori, details, mil, jaati, hain:
const order = await Order.findOne({ _id: orderId }).populate("customer");
console.log(order.customer.name); // directly access, kar, sakte, hain- ref option = field, KIS, model, ko, reference, karta, hai, DEFINE, karta, hai
- populate() = reference, ki, JAGAH, ACTUAL, related, data, fetch, karके, embed, karta hai
- Internally, ek, ALAG, query, chalati, hai — multiple, nested, populate, PERFORMANCE, HURT, kar, sakti, hai
populate(), MULTIPLE, times, chain, kiya, ja, sakta hai, YA, EK, ARRAY, of, paths, PASS, kiya, ja, sakta hai, agar, EK, document, ke, MULTIPLE, reference, fields, ko, POPULATE, karna, ho.
const order = await Order.findById(orderId)
.populate("customer")
.populate("items.product");Virtual, populate, SE, "REVERSE" relationships, populate, ki, ja, sakti, hain — jaise, EK, User, ke, saare, Posts, (jinme, User, ki, _id, reference, hai) fetch, karna, bina, user, document, mein, POSTS, array, STORE, kiye.