SQL Server 2017 Developer's Guide

Defining masked columns

You define DDM at the column level. You can obfuscate values from a column in a table by using four different masking functions:

• The default function implements full masking. The mask depends on the data type of the column. A string is masked by changing each character of a string to X. Numeric values are masked to zero. Date and time data type values are masked to 01.01.2000 00:00:00.0000000 (without double quotes). Binary data is masked to a single byte of ASCII value 0.
• The email function masks strings that represent e-mail addresses in the form: [e-mail].
• The random function masks numeric values to a random value in a specified range.
• The partial function uses a custom string to mask character data. You can ...