Using Union to bring in only new records

[IgorGershenson]

Hi,  I am using the Union function in DAX to append one table to another. I would love to only append those email records in table 2 to table  1 that don't already exist in table 1. What is the best way to do this or does the Union function do this automatically?  So in the example below, I want the final product to show emails 2 and 3 once (not twice) after I apply the Union function to these two tables. Thank you so much!

Table 1			Table 2
Email	Campaign		Email	Campaign
1	Online Ad1		223	Webinar
2	Online Ad2		2	Online Ad2
3	Online Ad3		3	Online Ad3
			4	Online Ad4
			5	Online Ad5

[IgorGershenson]

Thank you!

[CNENFRNL · Accepted solution]