Delete Data

 

DynamoDB তে data delete করার syntax 

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1️⃣ AWS CLI – delete-item

Syntax:

aws dynamodb delete-item \
    --table-name TableName \
    --key '{"PartitionKeyName": {"S": "value"}, "SortKeyName": {"S": "value"}}' \
    --endpoint-url http://localhost:8000

--key → Partition Key + Sort Key (যদি থাকে)

--endpoint-url → Local Docker DynamoDB address

Example: Delete a user with user_id = 1

aws dynamodb delete-item \
    --table-name Users \
    --key '{"user_id": {"S": "1"}}' \
    --endpoint-url http://localhost:8000

✅ Optional: ConditionExpression ব্যবহার করলে নিশ্চিত করা যায় শুধু যখন কিছু condition সত্য হয় তখনই delete হবে

aws dynamodb delete-item \
    --table-name Users \
    --key '{"user_id": {"S": "1"}}' \
    --condition-expression "attribute_exists(user_id)" \
    --endpoint-url http://localhost:8000

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2️⃣ Python – delete_item

import boto3

# Connect to local DynamoDB
dynamodb = boto3.resource('dynamodb', endpoint_url='http://localhost:8000', region_name='us-east-1')
table = dynamodb.Table('Users')

# Delete item
response = table.delete_item(
    Key={'user_id': '1'},  # Partition Key
    ConditionExpression="attribute_exists(user_id)"  # Optional
)

print("Deleted successfully!")

Key Points:

1. Key → Partition Key + Sort Key (যদি থাকে)

2. Optional: ConditionExpression → শুধু যখন record exist করে তখন delete

3. Large table এ একসাথে multiple delete করতে হলে loop + batch_writer() (for delete) ব্যবহার করা যায়

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3️⃣ Python  – Delete multiple items at a time

items_to_delete = ['2', '3', '4']  # user_id list

with table.batch_writer() as batch:
    for uid in items_to_delete:
        batch.delete_item(Key={'user_id': uid})

print("All selected items deleted!")

batch_writer() দিয়ে একসাথে multiple delete possible

Maximum 25 items per batch recommended

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🔑 Summary:

Operation	AWS CLI	Python boto3
Delete single	delete-item	delete_item()
Delete multiple	CLI loop + delete-item	batch_writer().delete_item()
Conditional delete	--condition-expression	ConditionExpression=...