Python / Boto3: Float Types Are Not Supported. Use Decimal Types Instead
I'm Using Python 3.7 to Store Data in a Dynamodb Database and Encountering the Following Error Message When I Try and Write an Item to the Database: Float...
I'm using Python 3.7 to store data in a DynamoDB database and encountering the following error message when I try and write an item to the database:
Float types are not supported. Use Decimal types instead.
My code:
ddb_table = my_client.Table(table_name)
with ddb_table.batch_writer() as batch:
for item in items:
item_to_put: dict = json.loads(json.dumps(item), parse_float=Decimal)
# Send record to database.
batch.put_item(Item=item_to_put)
"items" is a list of Python dicts. If I print out the types of the "item_to_put" dict, they are all of type str.
Thanks in advance for any assistance.
4 Answers
Convert all the float to the Decimal
import json
from decimal import Decimal
item = json.loads(json.dumps(item), parse_float=Decimal)
table.put_item(
Item=item
)
Ran into the same issue and it turned out that Python was passing a string parameter as something else. The issue went away when I wrapped all of the items in str().
Same issue here. In my case it was because some of my records did not have a certain key, and that key was being auto-added with nan by default(I guess?). I added some simple logic to check if that key was a list and set it to an empty list if not before running batch.put_item which has seemingly satisfied the Dynamo beast.
Add: from decimal import Decimal above the expression. This should fix the problem
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