Get obfuscated value about my_obfuscate

[oenie]

I don't think you can get the obfuscated value from the first line into the 2nd to 4th.
Right now your proc is just copying the value you found in the original dump.
What I did is use a proc that returns a combination of md5 hash function on the username column:

require "digest"

...
:users => {
    :username => { :type => :fixed, :string => proc { |row| (Digest::MD5.hexdigest row[:username]) + '@hashed.be' } },
    :username_canonical => { :type => :fixed, :string => proc { |row| (Digest::MD5.hexdigest row[:username]) + '@hashed.be' } },
    :email => { :type => :fixed, :string => proc { |row| (Digest::MD5.hexdigest row[:username]) + '@hashed.be' } },
    :email_canonical => { :type => :fixed, :string => proc { |row| (Digest::MD5.hexdigest row[:username]) + '@hashed.be' } },
},
...

That way, all of your fields are using the same hashed value, somewhat solving your problem.