How to replace text in a comma separated column with new value

Hi vbowlen

Here is my solution. Add a custom column with below code. ReferenceDataTable is another table which has two columns "Reference" and "New ID", just like you have shown. Please notice that the first column should have old values and the second column should have new values. 

= Text.Combine(List.ReplaceMatchingItems(List.Transform(Text.Split([contract_communities_list], ","), Text.Trim), Table.ToRows(ReferenceDataTable)), ", ")

Here is a blog for your reference: Replace Values in Power Query M (Ultimate Guide) - BI Gorilla

Best Regards,
Jing
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