In CRM Analytics, when dealing with two datasets, such as Dataset A (activities) and Dataset B (users), and you want to delete records from Dataset A based on the users listed in Dataset B, you would typically use a combination of a join and filter transformation in a recipe. The join transformation allows you to combine data from both datasets based on the shared userID dimension, and the filter transformation would then be used to delete or exclude any activities from Dataset A that are associated with the users from Dataset B. This approach ensures that only relevant activities remain in Dataset A after filtering out the unwanted ones.
Reference: CRM Analytics Recipes: Join and Filter Transformations