Getting all parent rows in one SQL query

Question

I have a simple MySQL table thats contains a list of categories, level is determined by parent_id:

id  name    parent_id
---------------------------
1   Home         


        

Answer 1

I used the previous answers as examples to make smth more readable.

SELECT  @org_id as id,
    (SELECT name FROM test.organizations WHERE id = @org_id) as name,
    (SELECT @org_id := parent_id FROM test.organizations WHERE id = @org_id) AS parent_id
FROM (SELECT @org_id := 4) vars, test.organizations org
WHERE @org_id is not NULL
ORDER BY id;

The result of execution looks like that:

(just for quick) to check it yourself you need to enter values from the question into database test, table organizations

CREATE TABLE organizations(
id        int(11) NOT NULL AUTO_INCREMENT,
name      varchar(45) DEFAULT NULL,
parent_id int(11)     DEFAULT NULL,
PRIMARY KEY (id));

insert into organizations values(1, "home", null);
insert into organizations values(2, "about", 1);
insert into organizations values(3, "contact", 1);
insert into organizations values(4, "legal", 2);
insert into organizations values(5, "privacy", 4);
insert into organizations values(6, "products", 1);
insert into organizations values(7, "support", 1);