Forum Discussion
Having problems with multiple date formats after last refresh
Hi ranz_vincent
When changing the data types, especially at the very beginning, always ensure that the culture is specified. Also, if you have any transformations that combines the date with another column, specify the culture as well.
en-AU and en-GB follows dd/mm/yy while en-US follows mm/dd/yy.
Hi ranz_vincent,
Thank you for reaching out to the Microsoft fabric community forum. Also thanks ajaybabuinturi, Nasif_Azam, for those valuable insights on this issue. I have identified few workarounds that may assist in resolving the thread.
Based on your description, it appears the problem arises from inconsistent date formats across your CSV files, likely introduced after recent edits. Power BI infers column types using the first file in your folder source, and any structural or formatting differences in other files can result in refresh errors, particularly with date parsing.
Please check all CSV files in the folder. Ensure they all use the same delimiter (comma, semicolon, etc.). Confirm that the date columns are in the same format, such as dd/mm/yyyy. When saving CSVs from Excel, avoid incompatible regional formats—save as CSV UTF-8 (Comma delimited) if using Excel.
Update Power Query Steps: Open Power Query Editor. In the Transform Sample File query: Remove or modify any automatic "Changed Type" step. Apply Change Type Using Locale instead:
Table.TransformColumnTypes(#"Previous Step", {{"YourDateColumn", type date}}, "en-GB")Use "en-GB" for dd/mm/yyyy format
To disable Auto-Type Detection, navigate to File > Options > Data Load and uncheck “Automatically detect column types and headers for unstructured sources.” If necessary, rebuild the Sample File Logic. If the issue continues, consider recreating the folder query using a verified CSV sample and then apply consistent transformation logic to all files.
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Hi ranz_vincent,
May I ask if you have resolved this issue? If so, please mark the helpful reply and accept it as the solution. This will be helpful for other community members who have similar problems to solve it faster.
Thank you.
Hi ranz_vincent,
I wanted to check if you had the opportunity to review the information provided. Please feel free to contact us if you have any further questions. If my response has addressed your query, please accept it as a solution and give a 'Kudos' so other members can easily find it.
Thank you.