Jeff Liu jeffyuhaoliu

## final4-js
/* The PostsDAO must be constructed with a connected database object */
function PostsDAO(db) {
    "use strict";

    /* If this constructor is called without the "new" operator, "this" points
     * to the global object. Log a warning and call it correctly. */
    if (false === (this instanceof PostsDAO)) {
        console.log('Warning: PostsDAO constructor called without "new" operator');
        return new PostsDAO(db);
    }

## final3.js
use enron
db.messages.update(
  {'headers.Message-ID': '<8147308.1075851042335.JavaMail.evans@thyme>'},
	{$addToSet: {
		"headers.To": "mrpotatohead@mongodb.com"
	}},
	{multi: true}
)

## final2.js
use enron
db.messages.aggregate([
  {
		$unwind: "$headers.To"
	},
	{
		$project: {
			"_id": 1,
			"headers.From": 1,
			"headers.To": 1

## final1.js
use enron
db.messages.find({$and: [{"headers.From": "andrew.fastow@enron.com"}, {"headers.To": "jeff.skilling@enron.com"}]}).count()

## final7-1.js
use photosharing
db.images.aggregate([
  {
		$unwind: "$tags"
	},
	{
		$match: { tags: 'kittens'}
	},
	{
		$group: {

## SampleCreateReplicaSet
sudo bash < create_replica_set.sh
mongo --port 27018 < init_replica.js

## 5.3
use hw5
db.grades.aggregate([
  {
		$unwind: "$scores"
	}
	,{
		$match: {
			"scores.type": { $ne: "quiz" }
		}
	}

## 5.2
use hw5
db.zips.aggregate([
  /* First group via sum up of the values of the cities with the same name
	this is because a city will have multiple zips therefore,
	multiple entries of cities with the same name */
	{
		$group: {
			_id: { state: "$state", city: "$city"},
			pop: { $sum: "$pop" }
		}

## 5.1
use blog
db.posts.aggregate([{
  $unwind: "$comments"
}, {
	$group: {
		_id: "$comments.author",
		postcount: {
			$sum: 1
		}
	}

## 4.3
[
  {
		"v" : 1,
		"key" : {
			"_id" : 1
		},
		"ns" : "blog.posts",
		"name" : "_id_"
	},
	{
	/* The PostsDAO must be constructed with a connected database object */
	function PostsDAO(db) {
	"use strict";

	/* If this constructor is called without the "new" operator, "this" points
	* to the global object. Log a warning and call it correctly. */
	if (false === (this instanceof PostsDAO)) {
	console.log('Warning: PostsDAO constructor called without "new" operator');
	return new PostsDAO(db);
	}
	use enron
	db.messages.update(
	{'headers.Message-ID': '<8147308.1075851042335.JavaMail.evans@thyme>'},
	{$addToSet: {
	"headers.To": "mrpotatohead@mongodb.com"
	}},
	{multi: true}
	)
	use enron
	db.messages.aggregate([
	{
	$unwind: "$headers.To"
	},
	{
	$project: {
	"_id": 1,
	"headers.From": 1,
	"headers.To": 1
	use enron
	db.messages.find({$and: [{"headers.From": "andrew.fastow@enron.com"}, {"headers.To": "jeff.skilling@enron.com"}]}).count()
	use photosharing
	db.images.aggregate([
	{
	$unwind: "$tags"
	},
	{
	$match: { tags: 'kittens'}
	},
	{
	$group: {
	sudo bash < create_replica_set.sh
	mongo --port 27018 < init_replica.js
	use hw5
	db.grades.aggregate([
	{
	$unwind: "$scores"
	}
	,{
	$match: {
	"scores.type": { $ne: "quiz" }
	}
	}
	use hw5
	db.zips.aggregate([
	/* First group via sum up of the values of the cities with the same name
	this is because a city will have multiple zips therefore,
	multiple entries of cities with the same name */
	{
	$group: {
	_id: { state: "$state", city: "$city"},
	pop: { $sum: "$pop" }
	}
	use blog
	db.posts.aggregate([{
	$unwind: "$comments"
	}, {
	$group: {
	_id: "$comments.author",
	postcount: {
	$sum: 1
	}
	}
	[
	{
	"v" : 1,
	"key" : {
	"_id" : 1
	},
	"ns" : "blog.posts",
	"name" : "_id_"
	},
	{