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Multiple Descendants in Family Relationships in PHP

In the previous lesson, a father could only have one son. This was achieved because the father had a relation son_id.

Now let a father have several sons. In this case, we can still make only one table, which will be related to itself. Only in the relation field we will store not the id of the son, but the id of the father. In this case, several users will be able to reference their father - and thus the father will have several sons:

users
id name father_id
1 user1 3
2 user2 3
3 user3 4
4 user4 null

You can get a user along with his father as follows:

SELECT users.name as user_name, fathers.name as father_name FROM users LEFT JOIN users as fathers ON fathers.id=users.father_id

Suppose we have users. Each user has a father and a mother. Describe the storage structure.

Write a query that will fetch a user along with his father and mother.

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