There are several solutions to your problem:

1. Upload a new dataset

set.csv

A,B
year,'[2010, 2004, 2005,...]'
language,'["English", "Spanish", "Portugues",...]'

where [...] is a JSON array

then in your schema you could do some voodoo magic to parse the JSON array into a Ruby list and choose a random reference... Sorry I just put myself to sleep for a second.

Don't do that. Not only would it be tedious and time consuming, but it would require you to limit yourself to a finite number of different years random options.

2. Use scripting

I have spent an inordinate amount of time over the last week testing the limits of Mockaroo's scripting engine. It is actually quite broad, including

sequence

• while
  

  i = 0
  num = this
  this = ""
  while i < num  do
     this += i.to_s + ", "
     i +=1
  end
  this = this



• until
  

  this = 0
  until random(0, 1) == 0
     this += 1
  end
  this = "there were " + this.to_s + " random 0's"



• each
  

  arr = this
  this = ""
  arr.each do |i|
     this += "#{i}..."
  end
  this = this



• etc... (give me a break ruby has a lot of repetition constructs )
  

selection

• if
  

  if this
    this = "it was true"
  else
    this = "it was false"
  end
  this = this



• case
  

  case this
     when 1..5
        this = "It's between 1 and 5"
     when 6
        this = "It's 6"
     else
        this = "You gave me '" + this.to_s + "' -- I have no idea what to do with that."
  end
  this = this



• unless
  

  unless this.downcase == this
     this = "'" + this + "' is an uppercase letter"
  else 
     this = "'" + this + "' is a lower case letter"
  end
  this = this

functions

def hello()
   return "hello"
end
this = hello()

Data Structures

• Array
  

  this = ['one fish', 'two fish', 'red fish', 'blue fish'][this - 1]



• Hash
  

  h = {
  'L'=>'Large',
  'M'=>'Medium',
  'S'=>'Small'
  }
  h.default = '??'
  
  this = h[this]

The most notable limitations which i have encountered are:
1. Cannot define classes (as far as I can tell)
2. No static variables (a field cannot reference previous records)
3. Can't see which sequential repetition this record is - my workaround
4. No access to reflection (really hampered my attempts to peek under the api's metaphorical hood)

Final thoughts

You can do an awful lot with this scripting API, it will fight you (a lot) sometimes but at the end of the day is greatest weakness is that sometimes it is actually too random (not an insult).

Examples

Note

You likely noticed that I always end my formulas by assigning this = ... (sometimes event this = this) I don't fully understand why but I have had some bugs occur in the past where formulas were not being evaluated. This seems to solve it. (I have no idea why).