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sqloracle-databasehierarchyconnect-by

CONNECT BY and START WITH clauses in oracle sql


I want hierarchical data for the test data given below. For user 'jones' it should fetch the below records. I am having problem with CONNECT BY and START WITH clauses. I also think there is some JOIN problem between menu_items AND role_menu_items tables.

for user and their corresponding roles i need to fecth below data

select  mi.id,  mi.NAME,mi.MEN_ID,mi.ICON,mi.ACTION--,r.NAME 
from
menu_items mi,
role_menu_items rmi,
roles r,
USERS U,
USER_ROLES UR
where
mi.ID=rmi.MIT_ID and
rmi.ROL_ID=r.id and
r.id=UR.ROLE_ID and
U.ID=UR.USER_ID and
U.NAME='jones'
start with mi.men_id is null
connect by   prior  mi.ID=mi.men_id

Output

1   Menu1           Menu1       /images/home.gif
3   Help            Help    
4   page1   a   1   page1   1   /images/email.gif
7   about   d   1   about   3

Insert into MENU_ITEMS (ID,NAME,SHORTCUT,DISPLAY_SEQUENCE,ACTION,MEN_ID,ICON) 
  values (1,'Menu1',null,null,'Menu1',null,'/images/home.gif');

Insert into MENU_ITEMS (ID,NAME,SHORTCUT,DISPLAY_SEQUENCE,ACTION,MEN_ID,ICON) 
  values (2,'Menu2',null,null,'Menu2',null,null);

Insert into MENU_ITEMS (ID,NAME,SHORTCUT,DISPLAY_SEQUENCE,ACTION,MEN_ID,ICON) 
  values (3,'Help',null,null,'Help',null,null);

Insert into MENU_ITEMS (ID,NAME,SHORTCUT,DISPLAY_SEQUENCE,ACTION,MEN_ID,ICON) 
  values (4,'page1','a',1,'page1',1,'/images/email.gif');

Insert into MENU_ITEMS (ID,NAME,SHORTCUT,DISPLAY_SEQUENCE,ACTION,MEN_ID,ICON) 
  values (5,'page2','b',2,'page2',1,null);

Insert into MENU_ITEMS (ID,NAME,SHORTCUT,DISPLAY_SEQUENCE,ACTION,MEN_ID,ICON) 
  values (6,'page3','c',1,'page3',2,'/images/photo.gif');

Insert into MENU_ITEMS (ID,NAME,SHORTCUT,DISPLAY_SEQUENCE,ACTION,MEN_ID,ICON) 
  values (7,'about','d',1,'about',3,null);

insert into ROLES (ID, NAME)
values (1, 'administrator');

insert into ROLES (ID, NAME)
values (2, 'user');

Insert into ROLE_MENU_ITEMS (ROL_ID,MIT_ID) values (1,4);
Insert into ROLE_MENU_ITEMS (ROL_ID,MIT_ID) values (1,5);
Insert into ROLE_MENU_ITEMS (ROL_ID,MIT_ID) values (1,6);
Insert into ROLE_MENU_ITEMS (ROL_ID,MIT_ID) values (1,7);
Insert into ROLE_MENU_ITEMS (ROL_ID,MIT_ID) values (2,4);
Insert into ROLE_MENU_ITEMS (ROL_ID,MIT_ID) values (2,7);

Insert into USER_ROLES (USER_ID,ROLE_ID) values (2,2);
Insert into USER_ROLES (USER_ID,ROLE_ID) values (1,1);
Insert into USER_ROLES (USER_ID,ROLE_ID) values (3,2);

Insert into USERS (ID,NAME,PASSWORD) values (2,'scott','scott');
Insert into USERS (ID,NAME,PASSWORD) values (1,'john','john');
Insert into USERS (ID,NAME,PASSWORD) values (3,'jones','jones');

Solution

  • bad scheme, but it is possible

    1. select all menu_id for user role


    select RMI.MIT_ID
    from ROLE_MENU_ITEMS RMI
       , ROLES R
       , USERS U
       , USER_ROLES UR
    where RMI.ROL_ID = R.ID
      and R.ID = UR.ROLE_ID
      and U.ID = UR.USER_ID
      and U.NAME = 'jones'
    

    2. reverse hierarhy query


    select MI.*
         , max(LEVEL) over () + 1 - level as rev_level
         , lpad(' ', (max(LEVEL) over () + 1 - LEVEL) * 3, ' ') || MI.NAME as LEVEL_NAME
         , rownum RN
    from MENU_ITEMS MI
    connect by prior MEN_ID = ID
    start with ID IN (select RMI.MIT_ID
                      from ROLE_MENU_ITEMS RMI
                         , ROLES R
                         , USERS U
                         , USER_ROLES UR
                      where RMI.ROL_ID = R.ID
                        and R.ID = UR.ROLE_ID
                        and U.ID = UR.USER_ID
                        and U.NAME = 'jones')
    

    3. reverse (reverse hierarhy query)


    select ID
         , NAME
         , SHORTCUT
         , DISPLAY_SEQUENCE
         , ACTION
         , MEN_ID
         , ICON
         , LEVEL_NAME
    from 
    (
        select MI.*
             , max(LEVEL) over () + 1 - level as rev_level
             , lpad(' ', (max(LEVEL) over () + 1 - LEVEL) * 3, ' ') || MI.NAME as LEVEL_NAME
             , rownum RN
        from MENU_ITEMS MI
        connect by prior MEN_ID = ID
        start with ID IN (select RMI.MIT_ID
                          from ROLE_MENU_ITEMS RMI
                             , ROLES R
                             , USERS U
                             , USER_ROLES UR
                          where RMI.ROL_ID = R.ID
                            and R.ID = UR.ROLE_ID
                            and U.ID = UR.USER_ID
                            and U.NAME = 'jones')
    )
    group by ID --distinct with order
           , name
           , SHORTCUT
           , DISPLAY_SEQUENCE
           , ACTION
           , MEN_ID
           , ICON
           , LEVEL_NAME
    order by min(-RN)
    

    possible to keep the sort of root items by ID, using a subquery

    select ID
         , NAME
         , SHORTCUT
         , DISPLAY_SEQUENCE
         , ACTION
         , MEN_ID
         , ICON
         , LEVEL_NAME
    from 
    (
        select ID
             , NAME
             , SHORTCUT
             , DISPLAY_SEQUENCE
             , ACTION
             , MEN_ID
             , ICON
             , MAX(LVL) OVER () + 1 - LVL
             , rpad(' ', (max(LVL) over () + 1 - LVL) * 3, ' ') || NAME as LEVEL_NAME
             , RN
        from (
            select MI.*
                 , rownum RN
                 , level LVL
            from MENU_ITEMS MI
            connect by prior MEN_ID = ID
            start with ID IN (select RMI.MIT_ID
                              from ROLE_MENU_ITEMS RMI
                                 , ROLES R
                                 , USERS U
                                 , USER_ROLES UR
                              where RMI.ROL_ID = R.ID
                                and R.ID = UR.ROLE_ID
                                and U.ID = UR.USER_ID
                                and U.NAME = 'jones')
            order siblings by -ID
        )
    )
    group by ID --distinct with order
           , name
           , SHORTCUT
           , DISPLAY_SEQUENCE
           , ACTION
           , MEN_ID
           , ICON
           , LEVEL_NAME
    order by min(-RN)