Dump, export and import of a data subset

gistfile1.txt

# dumping a data subset
mongodump --port 8080 --out /tmp/collection_name -d database_name -c collection_name --query '{"created_at" : {"$gte" : {"$date" : 1353578400000} }}'

# exporting a data subset
mongoexport --port 8080 --out /var/collection_name.json -d database_name -c collection_name --query '{"updated_at" : {"$gte" : {"$date" : 1353578400000} }}'

# importing a data subset
mongoimport --port 8080 -d database_name -c collection_name --upsert --file /var/deny/collection_name.json