Turiu lentele:

+----+---+---+
| id | a | b |
+----+---+---+
|  1 | 1 | 7 |
+----+---+---+
|  1 | 0 | 2 |
+----+---+---+
|  2 | 1 | 5 |
+----+---+---+
|  2 | 0 | 2 |
+----+---+---+
|  2 | 0 | 1 |
+----+---+---+

Reikia gauti reiksme:
id, suma

suma skaiciuojama taip: jeigu a reiksme 1 tai b su pliusiu, jeigu a reiksme 
0 tai b su minusu ir visi susisumuoja