mongo
show dbs
use <db name>
show collections
db.CollectionaName.find()
increase output using the following:
DBQuery.shellBatchSize = 3000
db.users.remove( {"_id": ObjectId("123456")});
Not needed. but in case:
db["data.for.more"].find()
db["data.for.more"].remove( {"_id": ObjectId("123456")});