How to perform a batch write to DynamoDB using boto3

This article will show you how to store rows of a Pandas DataFrame in DynamoDB using the batch write operations.

First, we have to create a DynamoDB client:

import boto3

dynamodb = boto3.resource('dynamodb', aws_access_key_id='', aws_secret_access_key='')
table = dynamodb.Table('table_name')

When the connection handler is ready, we must create a batch writer using the with statement:

with table.batch_writer() as batch:
   pass # we will change that

Now, we can create an iterator over the Pandas DataFrame inside the with block:

with table.batch_writer() as batch:
    for index, row in df.iterrows():
        pass # to be changed

We will extract the fields we want to store in DynamoDB and put them in a dictionary in the loop:

with table.batch_writer() as batch:
    for index, row in df.iterrows():
        content = {
            'field_A', row['A'],
            'field_B', row['B']
        }
        # there is still something missing

In the end, we use the put_item function to add the item to the batch:

with table.batch_writer() as batch:
    for index, row in df.iterrows():
        content = {
            'field_A', row['A'],
            'field_B', row['B']
        }
        batch.put_item(Item=content)

When our code exits the with block, the batch writer will send the data to DynamoDB.