Mongo DB Solution

The solution to HOMEWORK 4.1 M101JS: MongoDB FOR NODE.JS DEVELOPERS Suppose you have a collection with the following indexes: > db.products.getIndexes() [ { "v" : 1, "key" : { "_id" : 1 }, "ns" : "store.products", "name" : "_id_" }, { "v" : 1, "key" : { "sku" : 1 }, "unique" : true, "ns" : [...]

Final: Question 6 Suppose you have a collection of students of the following form: { "_id" : ObjectId("50c598f582094fb5f92efb96"), "first_name" : "John", "last_name" : "Doe", "date_of_admission" : ISODate("2010-02-21T05:00:00Z"), "residence_hall" : "Fairweather", "has_car" : true, "student_id" : "2348023902", "current_classes" : [ "His343", "Math234", "Phy123", "Art232" ] } Now suppose that basic inserts into the collection, which only [...]

Final: Question 4 Enhancing the Blog to support viewers liking certain commentsIn this problem, you will be enhancing the blog project to support users liking certain comments and the like counts showing up in the permalink page. Start by downloading Final4.zip and posts.json from the Download Handout link and loading up the blog dataset posts.json. [...]

Final: Question 3 In this problem, you will update a document in the Enron dataset to illustrate your mastery of updating documents from the shell. Please add the email address "mrpotatohead@mongodb.com" to the list of addresses in the "headers. To" array for the document with "headers.Message-ID" of "<8147308.1075851042335.JavaMail.evans@thyme>" After you have completed that task, please [...]

Final: Question 2 Please use the Enron dataset you imported for the previous problem. For this question, you will use the aggregation framework to figure out pairs of people that tend to communicate a lot. To do this, you will need to unwind the To list for each message. This problem is a little tricky [...]

The solution homework 3.3 M101JS: MongoDB for Node.js Developers Making your blog accept comments In this homework, you will add code to your blog so that it accepts comments. Download and unpack the files for this homework from the Download Handout link. You will be using the same code as you downloaded for homework 3.2, [...]

Making your blog accept posts In this homework, you will be enhancing the blog project to insert entries into the posts collection. After this, the blog will have basic functionality. It will allow you to add blog posts with a title, body, and tags and have it be added to the posts collection properly. We [...]

HOMEWORK: HOMEWORK 4.4 In this problem, you will analyze a profile log taken from a MongoDB instance. To start, please download sysprofile.json from Download Handout link and import it with the following command: mongoimport -d m101 -c profile < sysprofile.json Now query the profile data, looking for all queries to the students' collection in the [...]

HOMEWORK: HOMEWORK 4.2 Suppose you have a collection called tweets whose documents contain information about thecreated_at time of the tweet and the user's followers_count at the time they issued the tweet. What can you infer from the following explain output? > db.tweets.explain("executionStats").find({"user.followers_count":{$gt:1000}}).limit(10).skip(5000).sort( { created_at : 1 } ) { "queryPlanner" : { "plannerVersion" : 1, [...]

HOMEWORK: HOMEWORK 2.1 In this problem, you will be using an old weather dataset. Download weather_data.csv from the Download Handout link. This is a comma separated value file that you can import into MongoDB as follows: mongoimport –type csv –headerline weather_data.csv -d weather -c data You can verify that you've imported the data correctly by [...]

Getting error below while installing the moodle, How we can solve them? must be installed and enabled It is required that you store all your data in a Unicode format (UTF-8). New installations must be performed into databases that have their default character set as Unicode. If you are upgrading, you should perform the UTF-8 [...]

To establish a "parent-child" or a "master-detail" relationship between two tables having a common column, we make use of referential integrity constraints. To implement this, we should define the column in the parent table as a primary key and the same column in the child table as a foreign key referring to the corresponding parent [...]

(the principle behind attribute domains is similar to that behind typing of variables in programming languages.) We have seen that a domain of possible values must be associated with every attribute. We know a no of standard domain types and data and time types defined in SQL. Declaring an attribute to be of a particular [...]

(The rules that should not be violated while performing an operation on the database) Integrity constraints ensure that changes made to the database by authorized users do not result in a loss of data consistency. Thus, integrity constraints guard against accidental damage to the database. Simple Constraints are Key Constraints and forms of Relationships Constraints. [...]