pythonazureazure-cosmosdbazure-cosmosdb-sqlapi

How to insert bulk data into Cosmos DB in Python?

I'm developing an application in Python which uses Azure Cosmos DB as the main database. At some point in the app, I need to insert bulk data (a batch of items) into Cosmos DB. So far, I've been using Azure Cosmos DB Python SDK for SQL API for communicating with Cosmos DB; however, it doesn't provide a method for bulk data insertion.

As I understood, these are the insertion methods provided in this SDK, both of which only support single item insert, which can be very slow when using it in a for loop:

Is there another way to use this SDK to insert bulk data instead of using the methods above in a for loop? If not, is there an Azure REST API that can handle bulk data insertion?

Solution

  • The Cosmos DB service does not provide this via its REST API. Bulk mode is implemented at the SDK layer and unfortunately, the Python SDK does not yet support bulk mode. It does however support asynchronous IO. Here's an example that may help you.

    from azure.cosmos.aio import CosmosClient
import os

URL = os.environ['ACCOUNT_URI']
KEY = os.environ['ACCOUNT_KEY']
DATABASE_NAME = 'myDatabase'
CONTAINER_NAME = 'myContainer'

async def create_products():
    async with CosmosClient(URL, credential=KEY) as client:
        database = client.get_database_client(DATABASE_NAME)
        container = database.get_container_client(CONTAINER_NAME)
        for i in range(10):
            await container.upsert_item({
                'id': 'item{0}'.format(i),
                'productName': 'Widget',
                'productModel': 'Model {0}'.format(i)
            }
        )

    Update: I remembered another way you can do bulk inserts in Cosmos DB for Python SDK and that is using Stored Procedures. There are examples of how to write these, including samples that demonstrate passing an array, which is what you want to do. I would also take a look at bounded execution as you will want to implement this as well. You can learn how to write them here, How to write stored procedures. Then how to register and call them here, How to use Stored Procedures. Note: these can only be used when passing a partition key value so you can only do batches within logical partitions.