I have the function below in postgres which was working fine. but then i had to add other types, So i tried to add cases to it. But this isn't working as expected.

Basically what i am trying to do is if user is ALPHA then add the last 2 where clauses. If its a BETA then only use the second last clause and ignore the last where clause.

     ------ Old method without checking the logged in user role ------
     begin
         return query SELECT distinct(gl.user_id) as user_id, u.name_tx FROM contact_linking cl
         INNER JOIN group_contacts gc ON gc.contact_id = cl.contact_id
         INNER JOIN group_linking gl ON gl.group_id = gc.group_id
         INNER JOIN group_contacts_w gcw ON gcw.group_link_id = gl.group_link_id
         INNER JOIN users u ON u.user_id = gl.user_id
         WHERE cl.ref_contact_type_cd = 'PRIMARY' 
         AND cl.users_id = userId AND cl.activ_yn = 'Y' AND gl.activ_yn = 'Y' AND cl.contact_id IS NOT NULL
         AND gc.type LIKE 'ALPHA%'
         AND gcw.type = gc.type

         UNION ALL
         select userId as user_id; 
     end

    ---------- After adding new Type ----------
    begin
        return query SELECT distinct(gl.user_id) as user_id FROM contact_linking cl
        INNER JOIN group_contacts gc ON gc.contact_id = cl.contact_id
        INNER JOIN group_linking gl ON gl.group_id = gc.group_id
        INNER JOIN group_contacts_w gcw ON gcw.group_link_id = gl.group_link_id
        INNER JOIN users u ON u.user_id = gl.user_id
        WHERE cl.ref_contact_type_cd = 'PRIMARY' 
        AND cl.users_id = userId AND cl.activ_yn = 'Y' AND gl.activ_yn = 'Y' AND cl.contact_id IS NOT NULL
        AND CASE 
            WHEN 'ALPHA' = (SELECT ref_user_cd FROM users WHERE user_id = userId) THEN gc.type LIKE 'ALPHA%'
            WHEN 'BETA' = (SELECT ref_user_cd FROM users WHERE user_id = userId) THEN gc.type LIKE '