Answer
$set updates or adds fields without replacing the entire document.
Quick Answer
$set updates specific fields of a document without replacing the whole thing. db.users.updateOne({_id: id}, {$set: {name: "Alice", age: 30}}). Only the specified fields change; other fields stay intact. Without $set, if you pass a plain object MongoDB replaces the entire document (losing all other fields). Always use $set for partial updates.
S
SugharaIQ Editorial Team
Verified Answer
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Source: SugharaIQ