You can update or delete masking rules after you assign the rules to the target columns.
When you update or delete a masking rule, a warning message appears that contains the list of columns, plans, and data domains that contain the rule assignment. You can export the list of affected objects and save them in a .csv file.
If you update a masking rule, you change the properties within the masking rule. The changes do not take effect in the plans that contain the rules. You must fix the changes in the plan, and generate and run the plan again. If you make changes in the name or type of the field of a custom masking rule, the assignments do not contain the changes. You must import the mapplet again.
If you delete masking rules, TDM does not delete the masking rule from the columns, data domains, and plans that contain the rule assignment. To update the changes in a plan, you must generate and run the plan again.