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Exercise

Masking identifying information with regular expressions

Regular expressions can also be used to replace patterns in strings using REGEXP_REPLACE(). The function is similar to the REPLACE() function. Its signature is REGEXP_REPLACE(source, pattern, replace, flags).

  • pattern is the string pattern to match in the source string.
  • replace is the replacement string to use in place of the pattern.
  • flags is an optional string used to control matching.

For example, REGEXP_REPLACE(xyz, '\d', '_', 'g') would replace any digit character (\d) in the column xyz with an underscore (_). The g ("global") flag ensures every match is replaced.

To protect parking violation recipients' privacy in a new web report, all letters in the plate_id column must be replaced with a dash (-) to mask the true license plate number.

Instructions

100 XP
  • Use REGEXP_REPLACE() to replace all uppercase letters (A to Z) in the plate_id column with a dash character (-) so that masked license plate numbers can be used in the report.