The batch_write_item operation in DynamoDB allows you to write multiple items to one or more tables in a single API call. This operation is useful when performing multiple write operations simultaneously to improve efficiency and reduce network latency.

When using batch_write_item, you can specify up to 25 items to be written or deleted in a single request. You can mix different operations (e.g., put, delete) within the same batch, and each operation has its item to be processed. All the operations within a single batch are processed atomically. If any individual write operation fails, the entire batch write is rolled back, preserving the atomicity.

It’s important to note that using batch_write_item can offer significant performance improvements over individual write operations. You can achieve faster data processing and better resource utilization by reducing the number of API calls.

In the next section, we will dive into practical examples of how to use batch_write_item and leverage the power of Boto3 and DynamoDB to handle large datasets efficiently.

Using batch_write_item

Let’s explore practical examples of how to use the batch_write_item operation in Python with Boto3.

To begin, you must create a list of item operations you want to perform in the batch. Each item operation consists of a PutRequest or a DeleteRequest object, depending on if you wish to write or delete items.

Here’s an example of creating a batch of put requests:

import boto3
dynamodb = boto3.client('dynamodb')
requests = []
    'PutRequest': {
        'Item': {
            'id': {'N': '1'},
            'name': {'S': 'John'},
            'age': {'N': '30'}
    'PutRequest': {
        'Item': {
            'id': {'N': '2'},
            'name': {'S': 'Jane'},
            'age': {'N': '25'}

In the above example, we create a list of two put requests, each containing an item with attributes such as id, name, and age.

To execute the batch write operation, call the batch_write_item method and pass the list of requests:

response = dynamodb.batch_write_item(
        'TableName': requests

The response object will provide information about the outcome of the batch write operation, including any unprocessed items.

Now you understand how to use batch_write_item with Boto3 in Python. The next section will explore some best practices to optimize your data processing workflow.

Best Practices for Efficient Data Processing

When using the batch_write_item operation in Boto3 DynamoDB, there are several best practices you can follow to ensure optimal performance and efficiency:

  • Group Related Items: If possible, group related items together in a single batch. This can help minimize the number of write requests and optimize the data processing.
  • Consider Batch Size: While you can include up to 25 items in a batch, finding the right balance is essential. Experiment with different batch sizes to determine the optimal number of items to include based on your specific workload and performance requirements.
  • Handle Unprocessed Items: When executing a batch write operation, there might be cases where some items fail to process. You can retrieve the unprocessed items from the response and take appropriate action to handle those items separately.
  • Monitor and Benchmark: Monitor the performance and throughput of your batch write operations. Use CloudWatch metrics and benchmarking tools to gain insights into the impact of batching on your application’s performance.
  • Consider Provisioned Throughput: Ensure that your DynamoDB table has enough provisioned throughput capacity to handle the increased workload from batch write operations. Monitor your table’s capacity and adjust it as necessary.

By following these best practices, you can optimize your data processing workflow and maximize the efficiency of the batch_write_item operation in Boto3 DynamoDB.

In the concluding section, we will summarize the key points discussed in this blog post and provide references for further exploration.


What is the difference between batch_write_item and batch_writer?

BatchWriteItem and BatchWriter are two methods used in Amazon’s DynamoDB for batch operations. BatchWriteItem is a low-level API method that enables you to put or delete several items across multiple tables in a single API call. However, the complexity lies in handling unprocessed items and exceptions. On the other hand, BatchWriter is a high-level API provided by boto3, the AWS SDK for Python, that abstracts the details of adding automatic retries and handling unprocessed items. BatchWriter simplifies batch operations, managing the complexity under the hood while offering an easier interface for writing multiple items.

What is the benefit of batch write in DynamoDB?

Batch writing in DynamoDB, through the BatchWriteItem command, offers improved efficiency and reduced costs for bulk operations. It allows you to perform multiple PutItem and DeleteItem operations in a single network round trip, which enhances throughput and reduces latency. Moreover, because DynamoDB charges based on the amount of data read or written, not the number of requests, batch operations can lead to cost savings for large-scale operations. This bulk operation strategy is especially beneficial in applications where you must write or delete large amounts of data quickly and efficiently.

What is the difference between transact write and batch write in DynamoDB?

TransactWriteItems and BatchWriteItem are two operations in DynamoDB with key differences. BatchWriteItem allows multiple PutItem and DeleteItem operations across different tables in one API call, optimizing network round trips. However, if any operation fails, DynamoDB doesn’t roll back the successful ones. Conversely, TransactWriteItems provides a transactional guarantee, meaning that all operations (Put, Update, Delete, or ConditionCheck) within the transaction either succeed together or fail together, ensuring data integrity. However, TransactWriteItems only supports operations on items within a single AWS account and region and costs more than a standard write.


In this blog post, we have explored the batch_write_item operation in Boto3 DynamoDB. We started with an introduction to Boto3 and DynamoDB, followed by a step-by-step guide to getting started with Boto3 and configuring the DynamoDB client.

We then delved into the details of the batch_write_item operation, understanding its purpose and benefits. We provided examples of how to use the operation in Python using Boto3, demonstrating how to create batches of put requests and execute the batch write operation.

Furthermore, we discussed best practices for efficient data processing, including grouping related items, considering batch size, handling unprocessed items, monitoring performance, and provisioning adequate throughput capacity.

By following these guidelines, you can harness the power of batch_write_item in Boto3 DynamoDB to process data more efficiently and optimize the performance of your applications.

We hope this blog post has provided valuable insights and practical examples to leverage the batch_write_item operation effectively. Use Boto3 and DynamoDB batch writing to enhance your data processing workflow and make your applications more efficient.


Here are some helpful references and resources for further exploration:

These references provide comprehensive information and examples to help you deepen your understanding of Boto3, DynamoDB, and the batch_write_item operation.

Feel free to explore these resources to expand your knowledge and enhance your skills in working with Boto3 and DynamoDB.