Is there an "upsert" option in the mongodb insert command?
Since upsert
is defined as operation that "creates a new document when no document matches the query criteria" there is no place for upserts
in insert
command. It is an option for the update
command. If you execute command like below it works as an update
, if there is a document matching query
, or as an insert
with document described by update
as an argument.
db.collection.update(query, update, {upsert: true})
MongoDB 3.2 adds replaceOne
:
db.collection.replaceOne(query, replacement, {upsert: true})
which has similar behavior, but its replacement
cannot contain update operators.
As in the links provided by PKD, db.collection.insert()
provides no upsert possibility. Instead, mongo insert inserts a new document into a collection. Upsert is only possible using db.collection.update()
and db.collection.save()
.
If you happen to pass a document to db.collection.insert()
which is already in the collection and thus has an _id
similar to an existing _id
, it will throw a duplicate key exception.