with <name of you cte>(<column names>)as(<actual query>)select * from <name of your cte>

--菜單目錄結構表 create table tb_menu(  id int not null, --主鍵id title varchar(50), --標題  parent int --parent id ); --父菜單 insert into tb_menu(id, title, parent) values(1, '父菜單1',null); insert into tb_menu(id, title, parent) values(2, '父菜單2',null); insert into tb_menu(id, title, parent) values(3, '父菜單3',null); insert into tb_menu(id, title, parent) values(4, '父菜單4',null); insert into tb_menu(id, title, parent) values(5, '父菜單5',null); --一級菜單 insert into tb_menu(id, title, parent) values(6, '一級菜單6',1); insert into tb_menu(id, title, parent) values(7, '一級菜單7',1); insert into tb_menu(id, title, parent) values(8, '一級菜單8',1); insert into tb_menu(id, title, parent) values(9, '一級菜單9',2); insert into tb_menu(id, title, parent) values(10, '一級菜單10',2); insert into tb_menu(id, title, parent) values(11, '一級菜單11',2); insert into tb_menu(id, title, parent) values(12, '一級菜單12',3); insert into tb_menu(id, title, parent) values(13, '一級菜單13',3); insert into tb_menu(id, title, parent) values(14, '一級菜單14',3); insert into tb_menu(id, title, parent) values(15, '一級菜單15',4); insert into tb_menu(id, title, parent) values(16, '一級菜單16',4); insert into tb_menu(id, title, parent) values(17, '一級菜單17',4); insert into tb_menu(id, title, parent) values(18, '一級菜單18',5); insert into tb_menu(id, title, parent) values(19, '一級菜單19',5); insert into tb_menu(id, title, parent) values(20, '一級菜單20',5); --二級菜單 insert into tb_menu(id, title, parent) values(21, '二級菜單21',6); insert into tb_menu(id, title, parent) values(22, '二級菜單22',6); insert into tb_menu(id, title, parent) values(23, '二級菜單23',7); insert into tb_menu(id, title, parent) values(24, '二級菜單24',7); insert into tb_menu(id, title, parent) values(25, '二級菜單25',8); insert into tb_menu(id, title, parent) values(26, '二級菜單26',9); insert into tb_menu(id, title, parent) values(27, '二級菜單27',10); insert into tb_menu(id, title, parent) values(28, '二級菜單28',11); insert into tb_menu(id, title, parent) values(29, '二級菜單29',12); insert into tb_menu(id, title, parent) values(30, '二級菜單30',13); insert into tb_menu(id, title, parent) values(31, '二級菜單31',14); insert into tb_menu(id, title, parent) values(32, '二級菜單32',15); insert into tb_menu(id, title, parent) values(33, '二級菜單33',16); insert into tb_menu(id, title, parent) values(34, '二級菜單34',17); insert into tb_menu(id, title, parent) values(35, '二級菜單35',18); insert into tb_menu(id, title, parent) values(36, '二級菜單36',19); insert into tb_menu(id, title, parent) values(37, '二級菜單37',20);  --三級菜單 insert into tb_menu(id, title, parent) values(38, '三級菜單38',21); insert into tb_menu(id, title, parent) values(39, '三級菜單39',22); insert into tb_menu(id, title, parent) values(40, '三級菜單40',23); insert into tb_menu(id, title, parent) values(41, '三級菜單41',24); insert into tb_menu(id, title, parent) values(42, '三級菜單42',25); insert into tb_menu(id, title, parent) values(43, '三級菜單43',26); insert into tb_menu(id, title, parent) values(44, '三級菜單44',27); insert into tb_menu(id, title, parent) values(45, '三級菜單45',28); insert into tb_menu(id, title, parent) values(46, '三級菜單46',28); insert into tb_menu(id, title, parent) values(47, '三級菜單47',29); insert into tb_menu(id, title, parent) values(48, '三級菜單48',30); insert into tb_menu(id, title, parent) values(49, '三級菜單49',31); insert into tb_menu(id, title, parent) values(50, '三級菜單50',31); commit; 

--查詢樹狀結構某節點(44)的上級所有根節點  with cte_parent(id,title,parent)  as  (    --起始條件    select id,title,parent    from tb_menu    where id = 44  --列出子節點查詢條件    union all    --遞歸條件    select a.id,a.title,a.parent    from tb_menu a    inner join     cte_parent b     --執行遞歸，這里就要理解下了     on a.id=b.parent   )              select * from cte_parent; 

--查詢樹狀結構某節點下的所有子節點(  with cte_child(id,title,parent,level)  as  (    --起始條件    select id,title,parent,0 as level    from tb_menu    where id = 6--列出父節點查詢條件    union all    --遞歸條件    select a.id,a.title,a.parent,b.level+1    from tb_menu a    inner join     cte_child b    on ( a.parent=b.id)   )  select * from cte_child;