MongoDB cheatsheet

I've been dabbling quite a bit with MongoDB lately due to my new hobby (developing iPhone apps).

Here's my list of MongoDB cheatsheet for the commands I run pretty often:

DROPPING COLLECTIONS
db.yourcollection.drop();

DELETIONS
--To remove documents from a collection with ObjectId greater than a given id.
db.yourcollection.remove({"_id":{$gt:ObjectId("51212d98e4b07347c88e0f6f")}})

--To remove documents from a collection with a Column greater than a value

db.yourcollection.remove({yourcolumn:{$gt:50}})

--To remove documents from a collection with ObjectId given an id. 

db.yourcollection.remove({"_id":ObjectId("50ff1185e4b0f9e7d1c23586")});

IMPORT csv file into a collection in MongoDB

mongoimport -h yourmongodbhost -d database -c collection -u user -p password --type csv -f column1name,column2name --file c:\filename.csv

QUERYING

--find a document where ObjectId = an id

db.yourcollection.find({"_id":ObjectId("5101c346ade1db93e6f8bdff")})

--return first 10 rows 

db.yourcollection..find().sort({_id:1}).limit(10);

--return last 10 rows, if you want to return last row, just change to limit(1)

db.yourcollection..find().sort({_id:-1}).limit(10);