Data Masking Functions

Data masking refers to the process of distorting sensitive information based on masking rules to protect sensitive privacy data.

• mask_first_n(string str[, int n]) →varchar

  Description: Returns the masked version of a string. The first n values are masked. Uppercase letters are converted to X, lowercase letters to x, and digits to n.

  select mask_first_n('Aa12-5678-8765-4321', 4);
          _col0        
  ---------------------
   Xxnn-5678-8765-4321 
  (1 row)

• mask_last_n(string str[, int n]) →varchar

  Description: Returns the masked version of a string. The last n values are masked. Uppercase letters are converted to X, lowercase letters to x, and digits to n.

  select mask_last_n('1234-5678-8765-Hh21', 4);
          _col0        
  ---------------------
   1234-5678-8765-Xxnn 
  (1 row)     

• mask_show_first_n(string str[, int n]) →varchar

  Description: Returns the masked version of a string. Only the first n characters are displayed. Uppercase letters are converted to X, lowercase letters to x, and digits to n.

  select mask_show_first_n('1234-5678-8765-4321',4);
          _col0        
  ---------------------
   1234-nnnn-nnnn-nnnn 
  (1 row)

• mask_show_flairst_n(string str[, int n]) →varchar

  Description: Returns the masked version of a string. Only the last n characters are displayed. Uppercase letters are converted to X, lowercase letters to x, and digits to n.

  select mask_show_last_n('1234-5678-8765-4321',4);
          _col0        
  ---------------------
   nnnn-nnnn-nnnn-4321 
  (1 row))

• mask_hash(string|char|varchar str) →varchar

  Description: Returns a hash value of a string. Hash values are consistent and can be used to join masked values across tables. For a non-string, NULL is returned.

  select mask_hash('panda');
                                _col0                               
  ------------------------------------------------------------------
   a7cdf5d0586b392473dd0cd08c9ba833240006a8a7310bf9bc8bf1aefdfaeadb 
  (1 row)