MongoDB.md

MongoDB is:

• JSON storage
• schemaless
• NOT support SQL

Functionality that missing in MongoDB (in order to retain scalability):

• Joins between collections
• Transactions across multiple collections

Console tools

mongoimport -d course -c grades grades.json

Mongo Shell

mongo shell is a complete JavaScript environment so we can write: for (var i=0; i<10; i++) db.things.insert({index: i});

mongo script.js - run script

Collection Methods

• insert or save
• find
• find(...).pretty()
• findOne
• count
• update
• remove
• drop

BSON

Data constructors:

• NumberInt(1)
• NumberLong(4)
• ISODate("2012-10-21T17:20:09.759Z")

Cursurs

• sort({name:-1})
• limit(5)
• skip(10)

nodejs methods:

• each
• toArray

Update

• db.persons.update(criteria, newObj, options)
• db.persons.update(criteria, operatorObj, options)
• options: {multi:true}, {upset: true}
• $set
• $unset