I need to import (restore) a collection generated with mongodump
into an existing database and I'd like the records to be merged into the existing collection.
Does mongorestore
merge the records in the same collection or it will drop the existing collection before restoring the records?
mongorestore
will only drop the existing collection if you use the --drop
argument.
If you don't use --drop
, all documents will be inserted into the existing collection, unless a document with the same _id
already exists. Documents with the same _id
will be skipped, they are not merged. So mongorestore
will never delete or modify any of the existing data by default.