Re-writting the query without "Connect By " - sql

Question

I am rewriting the query to replace to remove CONNECT BY:
SELECT *
FROM ADM_TRT AT
INNER JOIN UTILISATEUR U
ON U.UTI_ID = AT.UTI_ID
INNER JOIN
(
SELECT CM.MAI_ID
FROM CON_MAI CM
CONNECT BY CM.MAI_PER_RES = PRIOR CM.MAI_ID
START WITH CM.MAI_ID IN (
SELECT MAJ_ID
FROM DROIT_LOGIN
WHERE LOG_ID = 21543
)
) CON_MAI_FILTERED_ON_LOGIN
ON AT.TRT_MAI_ID = CON_MAI_FILTERED_ON_LOGIN.MAI_ID;
For CONNECT BY Part , I wrote this
WITH tree (MAI_ID,MAI_PER_RES, level1) AS (
SELECT MAI_PER_RES, MAI_ID, 1 as level1 FROM CON_MAI
UNION ALL
SELECT child.MAI_ID, child.MAI_PER_RES, parent.level1 + 1
FROM CON_MAI child --Line 20
JOIN tree parent
on parent.MAI_PER_RES = child.MAI_ID
)
SELECT MAI_ID FROM tree
But I am stuck to integrate this in subquery in the CONNECT BY sub-query. Can someone please help to integrate this?

Answer 1

It looks like you have the recursion reversed in the recursive sub-query and can use:
WITH tree (MAI_ID) AS (
SELECT MAI_ID
FROM CON_MAI
WHERE MAI_ID IN ( SELECT MAJ_ID
FROM DROIT_LOGIN
WHERE LOG_ID = 21543 )
UNION ALL
SELECT c.MAI_ID
FROM CON_MAI c
JOIN tree p
on c.MAI_PER_RES = p.MAI_ID
)
SELECT *
FROM ADM_TRT AT
INNER JOIN UTILISATEUR U
ON U.UTI_ID = AT.UTI_ID
INNER JOIN tree CON_MAI_FILTERED_ON_LOGIN
ON AT.TRT_MAI_ID = CON_MAI_FILTERED_ON_LOGIN.MAI_ID;
(untested as I do not have your tables or data)