Decimal truncation when loading to Athena

Question

Hi,

Could you help to understand the reason why when loading data from Alteryx (2019.4.8 version) to Athena table decimals are truncated. In Select tool I set decimal to 40.10, but as a result in Athena table get for example such a value: 548.35. I have rechecked the workflow and each numeric column is set to 40.10.

Thank you in advance!

Oksana

BrandonB · Answer

Hi @OksanaBezpyata

This could potentially be related to the driver that you are using to load data, but can you please send this note to support@alteryx.com so that we can investigate further.

OksanaBezpyata · Answer

hi,

I have encountered one more interesting case related to loading decimals 38.12 to Athena by Alteryx.

I have the value 6187.905800000000 -> when loading to Athena it changes to 6187.9057999999995 in Athena.

Could you please let me know how I can fix it.

Thank you in advance!

Best regards,

Oksana

BrandonB · Answer

I may need double checked on this, but with Athena leveraging a bulk loader, it loads a CSV up to an S3 bucket to then be subsequently loaded into the Athena table. A CSV by nature will drop trailing zeroes off of a numeric data type decimal place. This would explain why although a fixed decimal is being used with a precision of 10, it isn't sending the extra zeroes to the Athena table if it is 548.3500000000