DataSource Error

[AyaneYep]

Guys, I'm getting this error message when applying the following transformation:

-Duplication of columns
-Transform row to column

OLE DB or ODBC error: [DataSource.Error] An error occurred while reading data from the provider: 'An item with the same key has already been added.'.

[v-yingjl · Accepted solution]

Hi @AyaneYep ,

Please check whether there existing some columns in the tables that share the same field name. If so, please rename these columns to enable each column has its unique field name. By the way, Table1.Column1 and Table2.Column2 might be regarded as the same one.

You can also refer the following similar case that could help you:

https://community.powerbi.com/t5/Desktop/Unexpected-error-An-item-with-the-same-key-has-already-been...

Best Regards,

Yingjie Li

If this post helps then please consider Accept it as the solution to help the other members find it more quickly.

[Greg_Deckler]

Please see this post regarding How to Get Your Question Answered Quickly: https://community.powerbi.com/t5/Community-Blog/How-to-Get-Your-Question-Answered-Quickly/ba-p/38490

Sounds like you already have a column with the same name as one trying to be created?