AWS CLI for DynamoDB - Mini Project: Build & Apply

AWS CLI for DynamoDB

📖 Scenario: You are working as a cloud engineer. Your team uses AWS DynamoDB to store user data. You need to practice using the AWS Command Line Interface (CLI) to manage DynamoDB tables and items.

🎯 Goal: Learn how to create a DynamoDB table, add items, query items, and update table settings using AWS CLI commands.

📋 What You'll Learn

Use AWS CLI commands to create and manage DynamoDB tables

Create a table with a primary key

Insert items into the table

Query items by primary key

Update table throughput settings

💡 Why This Matters

🌍 Real World

Managing DynamoDB tables and items via AWS CLI is common for automation, scripting, and quick management without using the AWS Console.

💼 Career

Cloud engineers and developers often use AWS CLI to manage DynamoDB resources efficiently in real projects.

1

Create a DynamoDB table

Use the AWS CLI command aws dynamodb create-table to create a table named Users with a primary key called UserId of type S (string). Set the read and write capacity units to 5 each.

DynamoDB

# Use aws dynamodb create-table with TableName 'Users', KeySchema with 'UserId' as HASH, AttributeDefinitions for 'UserId' as S, and ProvisionedThroughput with ReadCapacityUnits and WriteCapacityUnits set to 5
# Your code here

Hint

Remember to specify the table name, attribute definitions, key schema, and provisioned throughput exactly as shown.

2

Add an item to the Users table

Use the AWS CLI command aws dynamodb put-item to add an item to the Users table. The item should have UserId set to user123 and Name set to John Doe.

DynamoDB

aws dynamodb create-table --table-name Users --attribute-definitions AttributeName=UserId,AttributeType=S --key-schema AttributeName=UserId,KeyType=HASH --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5
# Use aws dynamodb put-item to add UserId 'user123' and Name 'John Doe' to the Users table
# Your code here

Hint

Use JSON format for the item attributes with correct data types.

3

Query the item by UserId

Use the AWS CLI command aws dynamodb get-item to retrieve the item from the Users table where UserId is user123.

DynamoDB

aws dynamodb create-table --table-name Users --attribute-definitions AttributeName=UserId,AttributeType=S --key-schema AttributeName=UserId,KeyType=HASH --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5
aws dynamodb put-item --table-name Users --item '{"UserId": {"S": "user123"}, "Name": {"S": "John Doe"}}'
# Use aws dynamodb get-item to get the item with UserId 'user123' from Users table
# Your code here

Hint

Use the --key option with JSON specifying the primary key to get the item.

4

Update the table's provisioned throughput

Use the AWS CLI command aws dynamodb update-table to change the Users table's read capacity units to 10 and write capacity units to 5.

DynamoDB

aws dynamodb create-table --table-name Users --attribute-definitions AttributeName=UserId,AttributeType=S --key-schema AttributeName=UserId,KeyType=HASH --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5
aws dynamodb put-item --table-name Users --item '{"UserId": {"S": "user123"}, "Name": {"S": "John Doe"}}'
aws dynamodb get-item --table-name Users --key '{"UserId": {"S": "user123"}}'
# Use aws dynamodb update-table to set ReadCapacityUnits to 10 and WriteCapacityUnits to 5 for Users table
# Your code here

Hint

Use the update-table command with the correct provisioned throughput values.

Practice

1. What does the AWS CLI command aws dynamodb list-tables do?

easy

A. It shows all DynamoDB tables in your AWS account and region.

B. It deletes all DynamoDB tables in your AWS account.

C. It creates a new DynamoDB table.

D. It updates the items in a DynamoDB table.

Solution

1. Step 1: Understand the command purpose

   The command aws dynamodb list-tables is designed to list existing tables, not modify or delete them.

2. Step 2: Match command to action

   Listing tables means showing all table names in your current AWS region and account.

3. Final Answer:

   It shows all DynamoDB tables in your AWS account and region. -> Option A

4. Quick Check:

   List tables = Show tables [OK]

Hint: List tables command always shows existing tables [OK]

Common Mistakes:

• Confusing list-tables with delete-table
• Thinking it creates or updates tables
• Assuming it shows table data instead of names

2. Which AWS CLI command syntax correctly adds an item to a DynamoDB table named Books with a primary key ISBN and a title attribute?

easy

A. aws dynamodb add-item --table Books --item '{ISBN: 12345, Title: Cloud Basics}'

B. aws dynamodb put-item --table-name Books --item '{"ISBN": {"S": "12345"}, "Title": {"S": "Cloud Basics"}}'

C. aws dynamodb insert-item --table-name Books --item '{"ISBN": "12345", "Title": "Cloud Basics"}'

D. aws dynamodb put-item --table Books --data '{"ISBN": "12345", "Title": "Cloud Basics"}'

Solution

1. Step 1: Identify correct command and parameters

   The correct command to add an item is put-item with --table-name and --item parameters.

2. Step 2: Check JSON format for item

   The item must be a JSON string with attribute names and types, e.g., {"ISBN": {"S": "12345"}} where "S" means string type.

3. Final Answer:

   aws dynamodb put-item --table-name Books --item '{"ISBN": {"S": "12345"}, "Title": {"S": "Cloud Basics"}}' -> Option B

4. Quick Check:

   Put-item + correct JSON format = aws dynamodb put-item --table-name Books --item '{"ISBN": {"S": "12345"}, "Title": {"S": "Cloud Basics"}}' [OK]

Hint: Use put-item with --item JSON including data types [OK]

Common Mistakes:

• Using wrong command like add-item or insert-item
• Missing data types in JSON attributes
• Using --table instead of --table-name

3. What will be the output of this AWS CLI command?

aws dynamodb get-item --table-name Users --key '{"UserId": {"S": "user123"}}' --projection-expression "Name, Age"

Assuming the table has an item with UserId 'user123', Name 'Alice', Age 30, and Email '[e-mail]'.

medium

A. Returns only the Email attribute.

B. Returns all attributes including Email.

C. Returns an error because projection-expression is invalid.

D. Returns only the Name and Age attributes of the item.

Solution

1. Step 1: Understand get-item with projection-expression

   The --projection-expression limits returned attributes to those listed, here "Name, Age".

2. Step 2: Check expected output

   Since Email is not in projection-expression, it will not be returned. Only Name and Age appear.

3. Final Answer:

   Returns only the Name and Age attributes of the item. -> Option D

4. Quick Check:

   Projection-expression filters attributes = Returns only the Name and Age attributes of the item. [OK]

Hint: Projection-expression returns only listed attributes [OK]

Common Mistakes:

• Assuming all attributes return by default
• Thinking projection-expression causes error
• Confusing projection-expression with filter-expression

4. You run this command but get an error:

aws dynamodb put-item --table-name Products --item '{"ProductId": "123", "Name": "Pen"}'

What is the likely cause of the error?

medium

A. The item JSON is missing data types for attributes.

B. The table name is incorrect.

C. The AWS CLI is not installed.

D. The command should use --update-item instead of --put-item.

Solution

1. Step 1: Check item JSON format requirements

   DynamoDB requires attribute values to specify data types, e.g., {"S": "123"} for string.

2. Step 2: Identify missing data types in JSON

   The command uses plain strings without data types, causing a syntax error.

3. Final Answer:

   The item JSON is missing data types for attributes. -> Option A

4. Quick Check:

   Missing data types in item JSON causes error [OK]

Hint: Always include data types like {"S": "value"} in item JSON [OK]

Common Mistakes:

• Ignoring data type syntax in item JSON
• Assuming --put-item is invalid command
• Not verifying table name correctness

5. You want to create a DynamoDB table named Orders with a primary key OrderId (string) and a sort key OrderDate (string). Which AWS CLI command is correct?

hard

A. aws dynamodb create-table --table-name Orders --attribute-definitions OrderId=S OrderDate=S --key-schema OrderId=HASH OrderDate=RANGE --provisioned-throughput Read=5,Write=5

B. aws dynamodb create-table --table Orders --attributes OrderId=S,OrderDate=S --keys OrderId=HASH,OrderDate=RANGE --throughput 5 5

C. aws dynamodb create-table --table-name Orders --attribute-definitions AttributeName=OrderId,AttributeType=S AttributeName=OrderDate,AttributeType=S --key-schema AttributeName=OrderId,KeyType=HASH AttributeName=OrderDate,KeyType=RANGE --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5

D. aws dynamodb create-table --table-name Orders --attributes OrderId S OrderDate S --key-schema OrderId HASH OrderDate RANGE --capacity 5 5

Solution

1. Step 1: Identify correct command syntax for create-table

   The correct syntax uses --attribute-definitions with AttributeName and AttributeType, and --key-schema with AttributeName and KeyType (HASH for partition key, RANGE for sort key).

2. Step 2: Check provisioned throughput format

   Provisioned throughput requires ReadCapacityUnits and WriteCapacityUnits with numeric values.

3. Final Answer:

   aws dynamodb create-table --table-name Orders --attribute-definitions AttributeName=OrderId,AttributeType=S AttributeName=OrderDate,AttributeType=S --key-schema AttributeName=OrderId,KeyType=HASH AttributeName=OrderDate,KeyType=RANGE --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5 -> Option C

4. Quick Check:

   Create-table syntax with attribute-definitions and key-schema = aws dynamodb create-table --table-name Orders --attribute-definitions AttributeName=OrderId,AttributeType=S AttributeName=OrderDate,AttributeType=S --key-schema AttributeName=OrderId,KeyType=HASH AttributeName=OrderDate,KeyType=RANGE --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5 [OK]

Hint: Use --attribute-definitions and --key-schema with correct keys [OK]

Common Mistakes:

• Using wrong flags like --table or --attributes
• Incorrect key schema format
• Wrong provisioned throughput parameter names