Data Masker for SQL Server is a great tool ensuring the data you use in non-production environments is compliant with any regulations by obfuscating and changing sensitive data. This is part of a series of posts on Data Masker from Redgate Software.
Recently I was testing a scenario for a customer and had an error while running an existing masking set. I had opened the set up and run it, a pre-test before I altered it for this customer. I immediately got this while running the masking set:
This is a common problem. Schemas evolve, and while fixing the data set should be part of the development and deployment process, the timing is difficult. I can’t change a masking set before the change is deployed into production. When it is, I don’t want to wait too long before I make the update.
In any case, when I click OK, I see the error location:
This isn’t that helpful, but if I click the “All Errors in the Masking Rules” tab, I get something that is useful.
This is the situation I described above. I had deployed part of a demo that moved data around and deleted a column. However, the masking set wasn’t changed. This makes sense as I often reset the demo, but in this case my copy of the database had the column.
Fixing the Error
I have two choices. I could add the column back, but that wouldn’t help with this post 
In this case, I’ll open rule 01-0013 by highlighting it and clicking “Edit Rule”, as shown below.
In this dialog, I see all the columns I’m masking. At the bottom, I can see the taxid, which doesn’t exist any longer. In this case, I can highlight the column and click the “Delete” button at the bottom.
I click “Update Substitution Rule” to save the changes and then I can run the entire set again. I’m looking for more errors, which are possible. In this case, I had to correct another column error. Then I got this:
Now I’m ready to actually set up the customer situation and help them fix their issue.
Data Masker is an incredibly powerful tool for protecting sensitive data. I see more and more customers using it all the time to comply with GDPR and other government regulations. If you’ve never tried it, download an eval today and check out our library of articles.