Add homework 2-2

Author: qmmr

hw2-2.js

@@ -0,0 +1,44 @@
+var MongoClient = require('mongodb').MongoClient
+
+MongoClient.connect('mongodb://127.0.0.1:27017/weather', function (err, db) {
+	if (err) throw err
+
+	var query = {}
+	var operator = { '$set': { 'month_high':true } }
+	// var options = { 'new': 1 }
+	var sort = [['State', 1], ['Temperature', -1]]
+
+	// var options = {
+	// 	'limit': 5,
+	// 	'sort': [['State', 1], ['Temperature', -1]]
+	// }
+
+	var cursor = db.collection('data').find().sort(sort)
+	var currentState = ''
+	var prevState = ''
+
+	cursor.each(function ( err, doc ) {
+		if (err) throw err
+
+		var query = {}
+
+		if (doc == null) return db.close()
+
+		if ( doc && doc.State !== currentState ) {
+			prevState = currentState
+			currentState = doc.State
+			console.log('change state from ' + prevState + ' to ' + currentState)
+
+			query['_id'] = doc['_id']
+			doc['month_high'] = true
+			console.log(query, doc)
+			db.collection('data').update(query, doc, function ( err, doc ) {
+				if (err) throw err
+				console.log(doc)
+				// return db.close()
+			})
+		}
+
+		// console.log(doc)
+	})
+})