
values. 
 
Verdict: The NULL’ing Out technique is useful in certain specific circumstances but 
rarely useful as the entire Data Sanitization strategy. 
 
 
Technique: Masking Data 
 
Masking data means replacing certain fields with a Mask character (such as an X). 
This effectively disguises the data content while preserving the same formatting on 
front end screens and reports. For example, a column of credit card numbers might 
look like: 
 
Data Sanitization Techniques                                  