Comparing two Dataset tags and removing excess rows

I have two different dataset tags both with the same amount of columns. For example my columns are labeled [“Project”, “Definition”, “Visual”] on both of my dataset tags. I would like to remove any rows on my old dataset that aren’t on the new dataset. If I have projects in my “Projects” column that exist in only my old dataset and not my new dataset I would like to remove those rows from the old dataset.

My old dataset has 40 rows and the new dataset has 30 rows so I would like my new dataset tag to have 30 rows and remove the 10 extra rows that dont match from the first dataset.

Could you just copy the new dataset to the old?