An item with the same key has already been added.

[hansei]

I am creating (my first) datamart, and am planning on using tables from a couple of different dataflows. I can create a datamart with table 'Payers' from dataflow 1. Separately, I can create a datamart with table 'Notes' from dataflow 2. Both of these dataflows exist in the same workspace as the intended datamart.

However, if I try create a datamart including both 'Payers' and 'Notes', they load into power query fine... but, when saving the datamart, an "InternalError" with message "An item with the same key has already been added" is received during the 'Wrapping things up' phase (after a successful 'Loading data' phase).

The dialog also reads "Your datamart is in a critical state. Please return back to the workspace" in red, and, when closed, the view ends up on the workspace. If an attempt is made to open the new datamart, an error message reading "The batch was submitted on the datamart 'GUID' that is not in an available status."

Unsure what all of this means. There is no relation between the tables. Both return empty lists if queried using Table.Keys().

[Shahfaisal]

I have seen that error occuring when there are two fields with the exact same name. Could you double-check if that is the case?

[hansei]

Do you mean two fields from the two different tables? That certainly occurs in my model e.g. primary keys and foreign keys from another table. If you mean within a single table, no.

The example models from Microsoft certainly have keys in multiple tables with the same name. e.g. In this model, Employees and Orders both have a field named EmployeeID. Similarly, Employees and Customers both have a field named Country.

Note again that my tables can be added individually without issue. The issue only arises when attempting to add both.

[smpa01]

@hansei  was it resolved? I have this error today.