HRMS run organizational structure (parent-child relationship)

Select Child_org.organization_id,
Child_org.name
From ( Select Org. Name,
Org. organization_id,
Pose_child.organization_id_parent,
Pose_child.organization_id_child
From Hr_all_organization_units org,
Per_org_structure_elements pose_child,
Per_org_structure_versions posv
Where Org. business_group_id =   202
And Pose_child.organization_id_child = Org. organization_id
And Trunc (sysdate) Between Trunc (posv. date_from) And
Trunc (nvl (posv. date_to, sysdate ))
And Posv. organization_structure_id =   940
And Posv.org _ structure_version_id =
Pose_child.org_structure_version_id) child_org
Start With Child_org.organization_id_parent =   204
Connect By Child_org.organization_id_parent = Prior
Child_org.organization_id_child