Forum Discussion
Unable to Change Data Type of String in PowerBI - Dataset Published via Alteryx Power BI Output Too
Hi,
We are publishing data from Alteryx Designer to Power BI Service using the Power BI Output Tool, which pushes data via the Power BI REST API.
During this process, we encountered a limitation documented by Alteryx:
“Due to Power BI API limitation, Designer can’t write DateTime values. Convert the DateTime values to strings before uploading the dataset to Power BI.”
(Source: Alteryx Power BI Output Tool Documentation
)
Following this guidance, we converted our DateTime field to string format (V_String / V_WString) before publishing.
The dataset now publishes successfully, and the field is visible in Power BI as text.
However, the issue is that inside Power BI, we are not able to change the data type of that string field back to Date or DateTime.
The dataset appears to be connected as a Live Connection (since it was created by the REST API).
The Transform Data / Power Query option is disabled.
We cannot switch the dataset to Import mode or DirectQuery.
Questions:
Is there any way to change the data type of a field (from String to Date) for a dataset that was published via the REST API?
Can a dataset created by an external connector (like Alteryx Power BI Output Tool) be converted to Import or DirectQuery mode in Power BI Desktop?
Any clarification or suggested workaround would be greatly appreciated.
Thanks,
Yes, the issue is now clear after reviewing the information provided by the contributors.
Since push datasets created through the REST API don’t support Power Query or transformations, the inability to change data types inside Power BI is expected behavior. Also, as confirmed, external tools like Alteryx cannot write directly into Dataflows because Dataflows do not expose a row-level write API.
At this point, it seems the only workable approach is to stage the data in an intermediate source such as Azure SQL, SharePoint/OneDrive, or Dataverse, and then use a Dataflow to perform proper transformations including DateTime conversion. We will explore these options on our side.
Thank you again for the clarification and guidance.
6 Replies
- DataVitalizer
Super User
Hi Junaid46
This behavior is expected with the Alteryx to Power BI REST API route.When you publish via the Power BI Output Tool, the dataset is created as a push dataset (streaming/live connection), push datasets don’t expose a Power Query layer, so you can’t transform columns or change data types inside Power BI that’s why the Transform Data option is disabled and why you can’t switch it to Import or DirectQuery mode afterward.
I suggest pushing the data into a Power BI dataflow (via Alteryx or another connector), then connecting your report to the dataflow. Dataflows support transformations and proper DateTime types.
Did it work? 👍 A kudos would be appreciated
🟨 Mark it as a solution to help spread knowledge 💡After reviewing available documentation, it looks like the Power BI Output Tool in Alteryx does not support writing to Dataflows. The Output Tool only supports pushing rows into Power BI datasets through the REST API, and Dataflows do not expose a write API for row ingestion.
If there is any supported way to send data directly into a Dataflow from a third-party tool like Alteryx, please let me know.
Thanks again for your clarification.
V-yubandi-msftCommunity Support
Hi Junaid46 ,
Thank you for checking. At the moment, Power BI Dataflows do not support pushing data directly via the REST API. Because of this, tools like Alteryx cannot write to Dataflows they can only send data to Power BI through push datasets. However, push datasets do not support Power Query or transformations.
If you need to perform transformations or handle fields like DateTime properly, a recommended approach is to first load your data into a source such as Azure SQL, SharePoint/OneDrive, or Dataverse. Then, you can connect your Dataflow to that source using Power Query.
Helpful Reference:
Dataflows - REST API (Power BI Power BI REST APIs) | Microsoft Learn
Connect to data sources for dataflows - Power Query | Microsoft Learn
Introduction to Dataflows and Self-service Data Prep - Power BI | Microsoft LearnRegards,
Yugandhar.
- V-yubandi-msft
Hi Junaid46 ,
Has the issue been resolved on your end, or would you like us to provide more information? Please let us know if you need any assistance.Yes, the issue is now clear after reviewing the information provided by the contributors.
Since push datasets created through the REST API don’t support Power Query or transformations, the inability to change data types inside Power BI is expected behavior. Also, as confirmed, external tools like Alteryx cannot write directly into Dataflows because Dataflows do not expose a row-level write API.
At this point, it seems the only workable approach is to stage the data in an intermediate source such as Azure SQL, SharePoint/OneDrive, or Dataverse, and then use a Dataflow to perform proper transformations including DateTime conversion. We will explore these options on our side.
Thank you again for the clarification and guidance.
- V-yubandi-msft
Good to hear the information helped and things are now clear.
Your idea to look into staging options like Azure SQL, SharePoint/OneDrive, or Dataverse, and then use Dataflows for transformations, is a strong and scalable strategy.
If you need more information or encounter any issues, feel free to reach out. We're here to support you and appreciate your active participation in the community.
Thank You.
