DynamoDB

Task 1 - Setup and Basic CLI Operations with DynamoDB Local

Start your DynamoDB local container

Run your Docker Compose file to launch DynamoDB locally:

docker-compose up -d

install AWS CLI

AWS CLI lets you interact with DynamoDB and other AWS services via terminal.

curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
unzip awscliv2.zip
sudo ./aws/install

Confirm installation

aws --version

Configure AWS CLI for local DynamoDB

You don’t need real AWS creds here, just configure creds to avoid errors:

aws configure

You will be prompted for the following:

AWS Access Key ID [None]: fakeMyKeyId
AWS Secret Access Key [None]: fakeSecretAccessKey
Default region name [None]: us-west-2
Default output format [None]: json

Create your DynamoDB table: Movies

add permission to the folder:

sudo chmod -R 777 ./docker/dynamodb

Create the table with a composite primary key (year as partition key, title as sort key):

aws dynamodb create-table \
    --table-name Movies \
    --attribute-definitions AttributeName=year,AttributeType=N AttributeName=title,AttributeType=S \
    --key-schema AttributeName=year,KeyType=HASH AttributeName=title,KeyType=RANGE \
    --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5 \
    --endpoint-url http://localhost:8000

Insert data into your table from the JSON file

aws dynamodb batch-write-item \
    --request-items file://movies.json \
    --endpoint-url http://localhost:8000

Select

Get all movies released in 2020:

aws dynamodb query \
    --table-name Movies \
    --key-condition-expression "#yr = :y" \
    --expression-attribute-names '{"#yr":"year"}' \
    --expression-attribute-values '{":y":{"N":"2020"}}' \
    --endpoint-url http://localhost:8000 \
    --no-paginate

Task 2 - CRUD Operations on Movies using AWS CLI

Retrieve one movie

aws dynamodb get-item \
  --table-name Movies \
  --key '{"year": {"N": "2020"}, "title": {"S": "The Last Stand"}}' \
  --endpoint-url http://localhost:8000 \
  --no-paginate | jq

Update a movie’s info attribute

aws dynamodb update-item \
  --table-name Movies \
  --key '{"year": {"N": "2020"}, "title": {"S": "The Last Stand"}}' \
  --update-expression "SET info = :i" \
  --expression-attribute-values '{":i": {"S": "Action thriller movie"}}' \
  --endpoint-url http://localhost:8000 \
  --return-values ALL_NEW | jq

Check the updated movie

Delete a movie

aws dynamodb delete-item \
  --table-name Movies \
  --key '{"year": {"N": "2019"}, "title": {"S": "Comedy Nights"}}' \
  --endpoint-url http://localhost:8000 \
  --no-paginate

Verify deletion

aws dynamodb get-item \
    --table-name Movies \
    --key '{"year": {"N": "2019"}, "title": {"S": "Comedy Nights"}}' \
    --endpoint-url http://localhost:8000 \
    --no-paginate | jq

Advanced Query

Get all movies from year 2020 whose title starts with "The" AND whose info contains "Action" (case-sensitive)

Task 3 - DynamoDB with Python

Install boto3

pip install boto3

Python script to create Actors table

The Actors table uses actor_id as partition key and movie_title as sort key.

import boto3

# Connect to local DynamoDB
dynamodb = boto3.resource('dynamodb', endpoint_url='http://localhost:8000', region_name='us-west-2')

# Create Actors table
table = dynamodb.create_table(
    TableName='Actors',
    KeySchema=[
        {'AttributeName': 'actor_id', 'KeyType': 'HASH'},  # Partition key
        {'AttributeName': 'movie_title', 'KeyType': 'RANGE'}  # Sort key
    ],
    AttributeDefinitions=[
        {'AttributeName': 'actor_id', 'AttributeType': 'S'},
        {'AttributeName': 'movie_title', 'AttributeType': 'S'}
    ],
    ProvisionedThroughput={'ReadCapacityUnits': 5, 'WriteCapacityUnits': 5}
)

table.wait_until_exists()
print(f"Table status: {table.table_status}")

Insert sample actors data

Create a new Python file insert_actors.py:

actors = [
    {'actor_id': 'a1', 'movie_title': 'The Last Stand', 'name': 'Arnold Schwarzenegger', 'role': 'Lead'},
    {'actor_id': 'a2', 'movie_title': 'The Last Stand', 'name': 'Forest Whitaker', 'role': 'Support'},
    {'actor_id': 'a3', 'movie_title': 'Comedy Nights', 'name': 'Comedian X', 'role': 'Lead'},
]

table = dynamodb.Table('Actors')
with table.batch_writer() as batch:
    for actor in actors:
        batch.put_item(Item=actor)

print("Actors inserted.")

Select actors from the table who played in "The Last Stand"

import boto3
from boto3.dynamodb.conditions import Attr

dynamodb = boto3.resource('dynamodb', endpoint_url='http://localhost:8000', region_name='us-west-2')
table = dynamodb.Table('Actors')

response = table.scan(
    FilterExpression=Attr('movie_title').eq('The Last Stand')
)

for actor in response['Items']:
    print(actor)

Delete an actor from the Actors table

Delete actor by actor_id and movie_title (primary key): 'actor_id': 'a1', 'movie_title': 'The Last Stand'

import boto3
from boto3.dynamodb.conditions import Key

dynamodb = boto3.resource('dynamodb', endpoint_url='http://localhost:8000', region_name='us-west-2')
table = dynamodb.Table('Actors')
response = table.delete_item(
    Key={
        'actor_id': 'a1',
        'movie_title': 'The Last Stand'
    }
)
print("Actor deleted.")

Select all actors from the Actors table

Scan movies released after a 2016 and whose title starts with "The"

Scan movies released after a 2016 and whose title starts with "The" and info contains "Action"