How to delete properties from an item in CosmosDB

June 16, 2022

I have a Python code to manage a collection in Cosmos DB by utilizing CosmosClient. It provides upsert_item, query_item, create_item, etc. But I need to delete properties from an existing item. Because the item could contain lots of properties, I wonder if there any better approach other than updating the whole item. I tried following code:

for i, item in enumerate(container.query_items(
        query='SELECT * FROM col c WHERE c._partitionKey="POLICY"',
        enable_cross_partition_query=True)):
    if (item["id"] == "$DEFAULT"):
        item['p1']=''
        item['p2']=''
        response = container.upsert_item(item)

This only updated p1 and p2 to empty string instead of deleting them. Anyone knows how to delete them programmatically? Since the partitionKey is POLICY, I couldn’t delete them in the portal.

>Solution :

To delete an item from a dictionary in Python, you will need to use del. So your code would be something like:

for i, item in enumerate(container.query_items(
        query='SELECT * FROM col c WHERE c._partitionKey="POLICY"',
        enable_cross_partition_query=True)):
    if (item["id"] == "$DEFAULT"):
        del item['p1']
        del item['p2']
        response = container.upsert_item(item)