I'm sorry I have not explained myself well.
I want to see the users that are not assigned the permision set.
I do not want to delete the users.
Thanks a lot
To identify the Users who are not assigned with Permission Set, please follow the below steps:
1) Login in to Dataloader and select the "Export" option.
2) Check the checkbox "Show all Salesforce objects" and select the "Permission Set Assignment" object.
3) Run the below query to get the list of Users assigned to a Permission set:
Select AssigneeId,PermissionSet.isOwnedByProfile FROM PermissionSetAssignment Where PermissionSet.isOwnedByProfile=False
4) Remove the duplicate records from the file generated in the above step in excel by selecting "Remove Duplicates" option under "Data".
5) Create a Report in Salesforce based on the User object to display the User Id and export it.
6) Perform a Vlookup between the files generated in Step 5 with Step 4 to get the list of Users who are not assigned to a Permission Set