Aggregation Performance
$match, aur, $sort, ko, PIPELINE, ke, SHURU, mein, RAKHNA, CHAHIYE — YE, INDEXES, ka, FAYDA, UTHA, sakte, HAIN, AGAR, WOH, PEHLE, STAGE, mein, HON, aur, DOWNSTREAM, STAGES, ke, liye, DATA, VOLUME, KAM, kar, dete, HAIN.
$project, se, JALDI, UNNECESSARY, FIELDS, REMOVE, karна, MEMORY, USAGE, KAM, karta hai — allowDiskUse: true, OPTION, se, LARGE, AGGREGATIONS, ko, DISK, USE, karne, ki, PERMISSION, milti, hai (100MB, memory, limit, se, ZYAADA, ke, liye).
// Optimized — match aur sort, PEHLE, indexed field par:
db.orders.aggregate([
{ $match: { status: "completed" } }, // Indexed field, PEHLE
{ $sort: { createdAt: -1 } },
{ $limit: 100 },
{ $lookup: { ... } } // expensive, stage, BAAD mein
], { allowDiskUse: true });- $match/$sort, ko, PIPELINE, ke, SHURU, mein, rakho — index, use, ho, sakta hai
- $project, se, jaldi, unnecessary, fields, remove, karna, memory, save, karta hai
- allowDiskUse: true = large aggregations, ke, liye, memory, limit, se, bachne, ke, liye
Agar, EK, PIPELINE, mein, $sort, ke, baad, sirf, TOP, N, results, chahiye, $limit, ko, JITNA, JALDI, ho, sake, laga, do (especially, expensive, stages, jaise, $lookup, se, PEHLE) — data, volume, KAAFI, kam, ho, jaata hai downstream, processing, ke, liye.
db.orders.aggregate([
{ $sort: { amount: -1 } },
{ $limit: 10 }, // pehle, limit
{ $lookup: { ... } } // phir, expensive, lookup — sirf, 10, docs, PAR
]);$facet, se, MULTIPLE, DIFFERENT, aggregation, pipelines, EK, hi, SET, of, input, documents, PAR, PARALLEL, mein, run, kiye, ja, sakte, hain — jaise, EK, hi, query, mein, "results" aur, "totalCount" (pagination, ke, liye) DONO, nikalna.