Mongorestore to update records if already exists without --drop

Question

I have a huge dump of collection of data which i have to transfer to another machine every weekend. So i'm planning for an incremental backup and restore. As experimented, mongorestore never merges data if _id already exists. Based on the above problem i tried using mongoimport and export with but the same problem exists as the existing records are not merged. Any possible solution would be helpfull.

error in mongoimport command caused by :: 11000 E11000 duplicate key error index: news.news_data.$id dup key: { : ObjectId('5404410d9f5323ef734dac68') }

Answer 1

The first case is true. Mongorestore does not update documents if already exist. It skips those documents when restoring. In your second case, please try using mongoimport with --upsert option. It will merge the records if _id already exists.

Example:

mongoimport --db dbname --collection collname --upsert --file file.json