Hi
I m thinking about combined key system. say i have mysql table having field
1. user_name
2. father_name
3. mother_name
4. Address
Now I can mark user_name field as key for unique value.
But I dont want that. I want that same user name is possible but same user name, father name and mother name combine is not possible. combined they must unique. mor easily
1. name01, father01,mother01
2. name01, father01,mother02
3. name01, father02,mother01
above data entry may be allow
But I want that
1. name01, father01,mother01
2. name01, father01,mother01
above data entry will not be allowed