journal
-------

id  | signature  | triple                   | valid_from   | valid_to
---------------------------------------------------------------------
1   |  A         | Florian eats Salad       | 1            |
2   |  B         | Salad is green           | 1            |
2   |  C         | Ben eats salad           | 1            |
2   |  D         | Green is a color         | 1            |
2   |  E         | Green is a beautiful     | 1            |
2   |  F         | Red is a color           | 1            |

Revision 1:
Florian   eats      Salad
Salad     is        green
Ben       eats      Salad
green     is_a      color
green     is_a      beautiful_color
red       is_a      color

2   |  A         | Florian eats Salad       | 2            | 2
2   |  G         | Florian eats Meat        | 2            |
2   |  H         | Florian eats Spaghetti   | 2            |
2   |  D         | green is a color         | 2            | 2
2   |  E         | green is a beautiful     | 2            | 2
2   |  I         | green is a ugly_color    | 2            |
2   |  B         | salad is green           | 2            | 2
2   |  J         | spaghetti is pasta       | 2            |
2   |  B         | ben eats salad           | 2            | 2


























Revision 2:
Florian   eats      Meat
Florian   eats      Spaghetti
Spaghetti is_a      Pasta
green     is_a      ugly_color
red       is_a      color

2   |  A         | Florian eats salad       | 3            |
2   |  L         | Ben eats Fish            | 3            |
2   |  I         | Green is ugly_color      | 3            | 3


Revision 3:
Florian   eats      Salad
Ben       eats      Fish
Florian   eats      Meat
Florian   eats      Spaghetti
Spaghetti is_a      Pasta
red       is_a      color