The option Persistent (P) is like Consistent (C). However, in this case the same values will be masked consistently across all the tables of the database. If the option persistent has been checked, then reference tables are created at the backend to ensure that any future masking operations yield consistent data masking.
Keeping data persistent can be helpful in retaining analysis results across a database, independent of when the data was collected, each time data is masked any similar values found will be masked identically. Persistent Masking is supported in RDBMS and RDS.
The Persistent (P) option can be used in conjunction with Consistent (C).
Persistent (P) + Consistent (C): This combination masks the data consistently within the column. The only difference is that, If the same task is executed again on the same column, then it will mask the newly added records consistently as per the previous task instance.
E.g., with reference to below image, the table displays the original names of all the customers before masking is applied with Persistent option.
In the below image, when masking is applied with Persistent option, the values in the cust_name are masked consistently across all the tables. Also, reference table is created at the backend which will store the mapping of original data with the masked values. This is done to ensure data consistency for future references if same values are encountered in the tables of the databases.
Here, if you would see that cust_name “Nikki” is masked with “Zia” and same will be stored in the reference table to ensure that whenever cust_name “Nikki” is encountered in the tables it should be masked with Zia.