How to create family tree database design?

Question

How can create tables and relationships for family tree?
I don’t want create table for each generation.
it’s not possible to use parent-child relationship because a child can be parent.

Answer 1

What we can say for sure, is that every person has exactly one father and one mother. So this can be solved with a single "person" table which contains all family members, with the reference to each parent in different fields.

Then you can build a hierarchical recursive query to find all ancestors of a child.

Answer 2

Family tree may have more than 5 generation, not just a father and mother and they children. And if use one table for many families with many rows its not good way.

Answer 3

it is a graph
one table of Persons
second table for relations:
Person1, Person2, relation_type

then you can list all near relations to Person1

Answer 4

zemiak can you explain more please

Answer 5

hamid
You can take a look here for more clues:
https://stackoverflow.com/questions/3897952/creating-a-list-tree-with-sqlite