Problem
When pulling data to Power BI we cannot refresh the data model due to the following error.
Data source error: Column '<oii>Item_ID</oii>' in Table '<oii>Items</oii>' contains a duplicate value '9999999' and this is not allowed for columns on the one side of a many-to-one relationship or for columns that are used as the primary key of a table. Table: Items.
Solution
The issue with duplicates usually happens because of some incorrect relationships or queries used in the Power BI data model.
To be more precise, please double-check the current connections and cardinality associated with the affected table.
You can try removing duplicates using Power Query. However, if the issue stems from relationships, this won't resolve the problem.