recursive CTE - hierarchy with parent, child, next

[Gabrielle Laurent]

Hello,

I have a hierarchy with parent, child and next id. The node_id of the hierarchy is not incremental, so my rows are sorted randomly. I need to query the hierarchy and sort it, I know I should use a recursive CTE but I have no idea how....
Could you help me ?

so I have this table :
CREATE TABLE GLT
(Node_id INT,
parent INT,
next INT,
child INT,
label VARCHAR(50));


INSERT INTO GLT (node_id, parent, next, child, label) VALUES
( 3 , 4 , 11 , 0 , 'A21' ),
( 4 , 8 , 0 , 3 , 'A2' ),
( 5 , 0 , 0 , 9 , 'C' ),
( 6 , 8 , 0 , 0 , 'A3' ),
( 7 , 9 , 25 , 0 , 'C11' ),
( 8 , 0 , 21 , 19 , 'A' ),
( 9 , 5 , 0 , 7 , 'C1' ),
( 10 , 21 , 0 , 0 , 'B1' ),
( 11 , 4 , 0 , 0 , 'A22' ),
( 19 , 8 , 4 , 0 , 'A1' ),
( 21 , 0 , 5 , 10 , 'B' ),
( 25 , 9 , 0 , 0 , 'C12' )


node_id / Parent / Next / Child / label
3 / 4 / 11 / 0 / A21
4 / 8 / 0 / 3 / A2
5 / 0 / 0 / 9 / C
6 / 8 / 0 / 0 / A3
7 / 9 / 25 / 0 / C11
8 / 0 / 21 / 19 / A
9 / 5 / 0 / 7 / C1
10 / 21 / 0 / 0 / B1
11 / 4 / 0 / 0 / A22
19 / 8 / 4 / 0 / A1
21 / 0 / 5 / 10 / B
25 / 9 / 0 / 0 / C12



and I would like the query to order it like this :

node_id / Parent / Next / Child / label
8 / 0 / 21 / 19 / A
19 / 8 / 4 / 0 / A1
4 / 8 / 0 / 3 / A2
3 / 4 / 11 / 0 / A21
11 / 4 / 0 / 0 / A22
6 / 8 / 0 / 0 / A3
21 / 0 / 5 / 10 / B
10 / 21 / 0 / 0 / B1
5 / 0 / 0 / 9 / C
9 / 5 / 0 / 7 / C1
7 / 9 / 25 / 0 / C11
25 / 9 / 0 / 0 / C12


and eventually add a column with an order sequence.

How should I do this ?

Thanks for your help

Gab