Assignments Of Day 19: MongoDB Data Import and Export

Assignment 1: Import JSON Data into MongoDB

Objective: Learn how to import a JSON file into a MongoDB collection.

Instructions:

1. Create a products.json file with the following content:

json

  { "product_name": "Laptop", "price": 1000, "category": "Electronics" },

  { "product_name": "Shirt", "price": 30, "category": "Clothing" }

2. Import this JSON file into a MongoDB database named shop and a collection named inventory.

Solution:

1. Save the products.json file with the content mentioned above.

2. Open the terminal and run the following mongoimport command:

bash

mongoimport --db shop --collection inventory --file products.json --type json --jsonArray

3. Explanation:

o --db shop: Specifies the database shop.

o --collection inventory: Specifies the collection inventory.

o --file products.json: Points to the products.json file.

o --type json: Specifies the data format as JSON.

o --jsonArray: Tells MongoDB that the JSON file contains an array.

4. Result: The data will be imported into the inventory collection in the shop database.

Assignment 2: Import CSV Data into MongoDB

Objective: Learn how to import CSV data into MongoDB.

Instructions:

1. Create a employees.csv file with the following content:

csv

name,age,department

John,30,Engineering

Jane,28,Marketing

2. Import this CSV file into the MongoDB database company and collection staff.

Solution:

1. Save the employees.csv file with the content mentioned above.

2. Open the terminal and run the following mongoimport command:

bash

mongoimport --db company --collection staff --file employees.csv --type csv --headerline

3. Explanation:

o --db company: Specifies the database company.

o --collection staff: Specifies the collection staff.

o --file employees.csv: Points to the employees.csv file.

o --type csv: Specifies the data format as CSV.

o --headerline: Uses the first row as field names.

4. Result: The CSV data will be imported into the staff collection in the company database.

Assignment 3: Import Data and Skip Duplicates

Objective: Learn how to prevent importing duplicate records during the import process.

Instructions:

1. Create a students.json file with the following content:

json

  { "name": "Alice", "age": 22, "major": "Physics" },

  { "name": "Bob", "age": 23, "major": "Mathematics" }

2. Import this data into a MongoDB database named university and a collection named students.

3. Run the import again, but ensure that any duplicate records are skipped.

Solution:

1. Save the students.json file.

2. Open the terminal and run the following mongoimport command:

bash

mongoimport --db university --collection students --file students.json --type json --jsonArray --upsert

3. Explanation:

o --upsert: Ensures that if the document already exists based on the _id, it will be updated; otherwise, a new document will be inserted. This helps to skip duplicates if they already exist.

o If you want to import data without creating duplicates based on a unique field, you can use an index on that field.

4. Result: If the data already exists in the collection, the --upsert flag will update it instead of duplicating.

Assignment 4: Import JSON Data with Nested Structure

Objective: Learn how to import JSON data with nested objects.

Instructions:

1. Create a orders.json file with the following content:

json

  { "order_id": "001", "customer": { "name": "John", "email": "john@example.com" }, "total": 150 },

  { "order_id": "002", "customer": { "name": "Jane", "email": "jane@example.com" }, "total": 200 }

2. Import this data into the MongoDB database shop and collection orders.

Solution:

1. Save the orders.json file.

2. Open the terminal and run the following mongoimport command:

bash

mongoimport --db shop --collection orders --file orders.json --type json --jsonArray

3. Explanation:

o MongoDB supports nested documents (like customer in this case) without any special handling.

o The nested structure will be preserved during import.

4. Result: The data with nested structures will be imported successfully into the orders collection.

Assignment 5: Export Data from MongoDB to JSON

Objective: Learn how to export data from a MongoDB collection to a JSON file.

Instructions:

1. Export all data from the students collection in the university database to a JSON file named students_export.json.

Solution:

1. Open the terminal and run the following mongoexport command:

bash

mongoexport --db university --collection students --out students_export.json --type json

2. Explanation:

o --db university: Specifies the database university.

o --collection students: Specifies the collection students.

o --out students_export.json: Specifies the output file students_export.json.

o --type json: Exports the data in JSON format.

3. Result: The entire students collection will be exported to the students_export.json file.

Assignment 6: Export Specific Fields from MongoDB

Objective: Learn how to export only specific fields from a MongoDB collection.

Instructions:

1. Export only the name and age fields from the students collection in the university database to a CSV file named students_partial.csv.

Solution:

1. Open the terminal and run the following mongoexport command:

bash

mongoexport --db university --collection students --out students_partial.csv --type csv --fields name,age

2. Explanation:

o --fields name,age: Specifies that only the name and age fields should be exported.

o --type csv: Specifies that the output format should be CSV.

3. Result: The name and age fields of the students collection will be exported to students_partial.csv.

Assignment 7: Filter Data During Export

Objective: Learn how to filter data during export using a query.

Instructions:

1. Export students who are older than 22 from the students collection in the university database to a JSON file.

Solution:

1. Open the terminal and run the following mongoexport command:

bash

mongoexport --db university --collection students --out filtered_students.json --type json --query '{"age": {"$gt": 22}}'

2. Explanation:

o --query '{"age": {"$gt": 22}}': Filters the data to export only students who are older than 22 years.

3. Result: The data for students who are older than 22 will be exported to filtered_students.json.

Assignment 8: Import CSV Data with Custom Delimiters

Objective: Learn how to import CSV data when using a custom delimiter.

Instructions:

1. Create a products.csv file with the following content, using | as the delimiter:

csv

product_name|price|category

Laptop|1000|Electronics

Shirt|30|Clothing

2. Import this data into MongoDB in the shop database and inventory collection.

Solution:

1. Save the products.csv file.

2. Open the terminal and run the following mongoimport command:

bash

mongoimport --db shop --collection inventory --file products.csv --type csv --headerline --fields product_name,price,category --delim "|"

3. Explanation:

o --delim "|": Specifies the custom delimiter (| in this case).

o --headerline: Uses the first row for field names.

4. Result: The data will be imported using the custom delimiter.

Assignment 9: Import Data with Field Mapping

Objective: Learn how to map fields while importing data into MongoDB.

Instructions:

1. Create a books.csv file:

csv

title,author,price

"The Great Gatsby",F. Scott Fitzgerald,10

"1984",George Orwell,15

2. Import this data into MongoDB, mapping the fields to book_title, book_author, and book_price.

Solution:

1. Save the books.csv file.

2. Open the terminal and run the following mongoimport command:

bash

mongoimport --db library --collection books --file books.csv --type csv --headerline --fields book_title=title,book_author=author,book_price=price

3. Explanation:

o --fields: Maps the original CSV columns to new field names in MongoDB.

4. Result: The fields in the MongoDB collection will be renamed according to the mappings provided.

Assignment 10: Export Data to BSON Format

Objective: Learn how to export data to BSON format.

Instructions:

1. Export all documents from the inventory collection in the shop database to a BSON file named inventory_export.bson.

Solution:

1. Open the terminal and run the following mongoexport command:

bash

mongoexport --db shop --collection inventory --out inventory_export.bson --type bson

2. Explanation:

o --type bson: Specifies the BSON format for the exported file.

o BSON (Binary JSON) is the native format used by MongoDB to store data.

3. Result: The data will be exported as a BSON file.

Assignments Of Day 19: MongoDB Data Import and Export