Removing data

[vivian123]

Hi all, 

What is the best way to remove rows based on a values in another column in this situation?

If there is more than one purchased item per customer then I want all data for that customer removed. 

Input table

Customer ID	Purchased item ID
123	666
123	999
234	111
456	888
789	555

Output table

Customer ID	Purchased item ID
234	111
456	888
789	555

Thanks

[Qiu · Accepted solution]

Maybe something like this.

[vivian123]

Thanks!!