oracle 迭代查询

 1 create table tbl_menu(
 2        id number primary key,
 3        parent_id number default 0,
 4        name varchar2(20) not null,
 5        direntions clob,
 6        info1 clob,
 7        info2 clob,
 8        info3 clob       
 9 );
10 
11 create sequence seq_tbl_menu;
12 
13 insert into tbl_menu (id, name, direntions) values (seq_tbl_menu.nextval, ‘虚拟根目录‘, ‘所有菜单的虚拟根目录其他所有菜单都直接或间接的是它的子菜单‘);
14 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 1, ‘权限管理‘);
15 
16 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 2, ‘资源管理‘);
17 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 2, ‘角色管理‘);
18 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 2, ‘用户管理‘);
19 
20 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 3, ‘菜单页面管理‘);
21 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 3, ‘非菜单页面管理‘);
22 
23 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 4, ‘角色管理‘);
24 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 4, ‘角色权限‘);
25 
26 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 5, ‘用户管理‘);
27 insert into tbl_menu (id, parent_id, name) values (seq_tbl_menu.nextval, 5, ‘用户权限‘);

 1 select
 2   id,
 3   parent_id,
 4   case 
 5     when parent_id = 0 then ‘------‘||name 
 6     when parent_id = 1 then ‘------------‘||name 
 7     when parent_id != 1 or parent_id != 0 then ‘------------------------‘||name
 8   else name end
 9 from tbl_menu 
10 start with id = 1
11 connect by prior id = parent_id
12 order by id