CSCI3287 Homework # 5 -- MongoDB Lab Solution

Overview


This assignment will give you hands-on practice in working with the MongoDB “NoSQL” database software.

Objectives
1. Download and install MongoDB
2. Create a MongoDB database to store a collection of documents
3. Load a large amount of document-based data into the collection
4. Query the document collection to research a topic and answer questions

Introduction:

The following links are helpful for an introduction MongoDB concepts and learning the basics of the MongoDB query language.

1. https://www.tutorialspoint.com/mongodb/mongodb_overview.htm : This link provides a basic overview of MongoDB and the basic queries for inserting documents, updating documents, query documents etc.


3. https://docs.mongodb.com/manual/introduction/ : The official MongoDB documentation page.






Installation:


First, you can install Docker. Then you can install MongoDB to run under Docker.

Or, if you prefer, you can simply download and install MongoDB on your PC (without using Docker.)

After you have installed MongoDB, you will import a “Big Data” dataset into your MongoDB instance and run some queries.

Query Exercises:

This document contains two sections. In the first, Section 1, you will have the opportunity to play with different basic operations in MongoDB. You can then use MongoDB with a realworld data set, and answer the questions below based on the data set in Section 2.

Section 1: Basic operations in MongoDB

1. Create a database: use DATABASE_NAME Ex: >use new_mongo_db

The above command will create a database if it does not exist and/or use the database if it already exists.

Replace DATABASE_NAME with the name of the database you want to create.

2. Drop a database: db.dropDatabase() Ex: >use new_mongo_db
switched to db new_mongo_db
>db.dropDatabase()

i. First you need to switch (with a “USE”) to the database to be dropped.
Then the above command will drop that database.

3. Creating a collection: db.createCollection(name, options)
Ex: >use new_mongo_db switched to db new_mongo_db
>db.createCollection("test_collection")
{ "ok" : 1 }

i. The above command creates the collection. But providing some initial additional options could be useful in certain circumstances. ii.
1. >db.createCollection("mycol", { capped : true, autoIndexId : true, size :
6142800, max : 10000 } )
{ "ok" : 1 }

2. For more information on the options, please check the following link.
https://docs.mongodb.com/manual/reference/method/db.cre ateCollection/

iii. In mongoDB, it is not necessary to create a collection. When a new document is inserted, mongoDB creates a collection automatically.

4. Dropping a collection: db.COLLECTION_NAME.drop()

Ex: >use new_mongo_db switched to db new_mongo_db
>db.test_collection.drop()
True
i.
ii. First you need to switch (with a “USE”) to the database, and then use the above command to delete the collection.
iii.
5. Insert a document: db.COLLECTION_NAME.insert(document) Ex: > db.test_collection.insert({
title: "Mongo Db practice", description: "this is my first MongoDB document"
})

Replace the COLLECTION_NAME with the name of the collection into which you wish to insert documents.

6. Query a document: db.COLLECTION_NAME.find()
i.
Ex: >db.test_collection.find().pretty()
ii. The above query will display the documents present in the collection.
iii. Try it with and without the “.pretty()” option.

7. Update a document: db.test_collection.update(SELECTION_CRITERIA, UPDATED_DATA)

Ex: >db.test_collection.update({'title':'MongoDB practice'},{$set:{ 'title':'Updated MongoDB practice'}})
i.
ii. The above example is used to update the documents that contain ‘title’ as
'MongoDB practice’ to 'Updated MongoDB practice’

8. Delete a Document: db.COLLECTION_NAME.remove(DELLETION_CRITERIA)

i. Remove only one record:
1. db.test_collection.remove({ status : "P" },1)
2. Here the first document which has this key value pair will be deleted.
ii. Remove all records matching a condition:
1. db.test_collection.remove({ status : "P" })
2. Here all the documents which have this key value pair will be deleted.


Section 2: Use a real-world data set to answer the seven questions below

1. Download the “primer-data.json” JSON dataset using the link found in the Week 14 Module.

2. From your Terminal type the following command to import the dataset into your Mongo collection.

mongoimport --db test --
~/Desktop/primer-data.json
collection restaurants --drop --file


The above mongoimport command converts the json file and stores it as a set of documents with the collection name of “restaurants”.

NOTE: This command is run in the Docker / Terminal Shell / Command Prompt, not within the Mongo interface.

ALSO NOTE: This command includes the name of your mongodb database (highlighted in GREEN above.) And it includes the name of your collection also highlighted in GREEN. If you changed the names of the database and/or collection as you did the import, you will have to change it in the import command string as well.

ALSO NOTE: This command points to the PATH where you put the file when you downloaded it (highlighted in BLUE above.) If you put it on your desktop, then the command should work as typed above. If you put the file elsewhere when you downloaded it, then you must modify the import command to point to the path where you put the file when you downloaded it.

Answer the following questions by writing queries and displaying the results.

(1) How many restaurants are there in this collection?

(2) List in alphabetical order each different (distinct) cuisine represented in this collection.

(3) Return the name of all restaurants within the zipcode 10023 which serve Italian cuisine. Return only the names of the restaurants.

(4) Which Borough has the most Greek restaurants? How many are there?

(5) Return a list of restaurants (names) which have the string “Pho ” in their name. (“Pho” is a wonderful and delicious Vietnamese noodle soup.)

(6) Return a list of boroughs ranked by the number of Italian restaurants in the borough. That is, for each borough, find how many restaurants serve Italian cuisine and print the borough and the number of such restaurants sorted descending by this number. (HINT: use the aggregate method, and use a $group and a $sum.)

(7) Find the top 5 Greek restaurants in Brooklyn that have the highest total score. Return for each restaurant the restaurant’s name and the total score. (HINT: use the aggregate method with $unwind to parse out the scores array, followed by a $group and a $sum.)


Submission Requirement:


For Section 2, screenshot or copy/paste your MongoDB command and output for each question. If the output exceeds 24 lines, just capture the first 24 lines.

Save your document as a PDF and upload to Canvas.


NOTES:


If you did work with a partner, be sure to specify your partner’s name on the document you submit.