站在用戶(hù)的角度思考問(wèn)題,與客戶(hù)深入溝通,找到南譙網(wǎng)站設(shè)計(jì)與南譙網(wǎng)站推廣的解決方案,憑借多年的經(jīng)驗(yàn),讓設(shè)計(jì)與互聯(lián)網(wǎng)技術(shù)結(jié)合,創(chuàng)造個(gè)性化、用戶(hù)體驗(yàn)好的作品,建站類(lèi)型包括:成都網(wǎng)站設(shè)計(jì)、成都網(wǎng)站制作、企業(yè)官網(wǎng)、英文網(wǎng)站、手機(jī)端網(wǎng)站、網(wǎng)站推廣、空間域名、網(wǎng)頁(yè)空間、企業(yè)郵箱。業(yè)務(wù)覆蓋南譙地區(qū)。
SQL Server 2005開(kāi)始,我們可以直接通過(guò)CTE來(lái)支持遞歸查詢(xún),CTE即公用表表達(dá)式
百度百科
公用表表達(dá)式(CTE),是一個(gè)在查詢(xún)中定義的臨時(shí)命名結(jié)果集將在from子句中使用它。每個(gè)CTE僅被定義一次(但在其作用域內(nèi)可以被引用任意次),并且在該查詢(xún)生存期間將一直生存??梢允褂肅TE來(lái)執(zhí)行遞歸操作。創(chuàng)建的語(yǔ)法是:
with <name of you cte>(<column names>)
as(
<actual query>
)
select * from <name of your cte>
生成數(shù)據(jù)
--菜單目錄結(jié)構(gòu)表 create table tb_menu( id int not null, --主鍵id title varchar(50), --標(biāo)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(jí)菜單 insert into tb_menu(id, title, parent) values(6, '一級(jí)菜單6',1); insert into tb_menu(id, title, parent) values(7, '一級(jí)菜單7',1); insert into tb_menu(id, title, parent) values(8, '一級(jí)菜單8',1); insert into tb_menu(id, title, parent) values(9, '一級(jí)菜單9',2); insert into tb_menu(id, title, parent) values(10, '一級(jí)菜單10',2); insert into tb_menu(id, title, parent) values(11, '一級(jí)菜單11',2); insert into tb_menu(id, title, parent) values(12, '一級(jí)菜單12',3); insert into tb_menu(id, title, parent) values(13, '一級(jí)菜單13',3); insert into tb_menu(id, title, parent) values(14, '一級(jí)菜單14',3); insert into tb_menu(id, title, parent) values(15, '一級(jí)菜單15',4); insert into tb_menu(id, title, parent) values(16, '一級(jí)菜單16',4); insert into tb_menu(id, title, parent) values(17, '一級(jí)菜單17',4); insert into tb_menu(id, title, parent) values(18, '一級(jí)菜單18',5); insert into tb_menu(id, title, parent) values(19, '一級(jí)菜單19',5); insert into tb_menu(id, title, parent) values(20, '一級(jí)菜單20',5); --二級(jí)菜單 insert into tb_menu(id, title, parent) values(21, '二級(jí)菜單21',6); insert into tb_menu(id, title, parent) values(22, '二級(jí)菜單22',6); insert into tb_menu(id, title, parent) values(23, '二級(jí)菜單23',7); insert into tb_menu(id, title, parent) values(24, '二級(jí)菜單24',7); insert into tb_menu(id, title, parent) values(25, '二級(jí)菜單25',8); insert into tb_menu(id, title, parent) values(26, '二級(jí)菜單26',9); insert into tb_menu(id, title, parent) values(27, '二級(jí)菜單27',10); insert into tb_menu(id, title, parent) values(28, '二級(jí)菜單28',11); insert into tb_menu(id, title, parent) values(29, '二級(jí)菜單29',12); insert into tb_menu(id, title, parent) values(30, '二級(jí)菜單30',13); insert into tb_menu(id, title, parent) values(31, '二級(jí)菜單31',14); insert into tb_menu(id, title, parent) values(32, '二級(jí)菜單32',15); insert into tb_menu(id, title, parent) values(33, '二級(jí)菜單33',16); insert into tb_menu(id, title, parent) values(34, '二級(jí)菜單34',17); insert into tb_menu(id, title, parent) values(35, '二級(jí)菜單35',18); insert into tb_menu(id, title, parent) values(36, '二級(jí)菜單36',19); insert into tb_menu(id, title, parent) values(37, '二級(jí)菜單37',20); --三級(jí)菜單 insert into tb_menu(id, title, parent) values(38, '三級(jí)菜單38',21); insert into tb_menu(id, title, parent) values(39, '三級(jí)菜單39',22); insert into tb_menu(id, title, parent) values(40, '三級(jí)菜單40',23); insert into tb_menu(id, title, parent) values(41, '三級(jí)菜單41',24); insert into tb_menu(id, title, parent) values(42, '三級(jí)菜單42',25); insert into tb_menu(id, title, parent) values(43, '三級(jí)菜單43',26); insert into tb_menu(id, title, parent) values(44, '三級(jí)菜單44',27); insert into tb_menu(id, title, parent) values(45, '三級(jí)菜單45',28); insert into tb_menu(id, title, parent) values(46, '三級(jí)菜單46',28); insert into tb_menu(id, title, parent) values(47, '三級(jí)菜單47',29); insert into tb_menu(id, title, parent) values(48, '三級(jí)菜單48',30); insert into tb_menu(id, title, parent) values(49, '三級(jí)菜單49',31); insert into tb_menu(id, title, parent) values(50, '三級(jí)菜單50',31); commit;
2.查找所有上級(jí)節(jié)點(diǎn)
--查詢(xún)樹(shù)狀結(jié)構(gòu)某節(jié)點(diǎn)(44)的上級(jí)所有根節(jié)點(diǎn) 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(jié)點(diǎn)查詢(xún)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(zhí)行遞歸,這里就要理解下了 on a.id=b.parent ) select * from cte_parent;
3.查找下級(jí)節(jié)點(diǎn)帶level
--查詢(xún)樹(shù)狀結(jié)構(gòu)某節(jié)點(diǎn)下的所有子節(jié)點(diǎn)( 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(jié)點(diǎn)查詢(xún)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;
參考文章
SQL Server 2008中的CTE遞歸查詢(xún) http://www.cnblogs.com/xfrog/archive/2010/10/10/1847462.html
Oracle 樹(shù)操作(start with…connect by…prior) http://www.cnblogs.com/linjiqin/archive/2013/06/24/3152674.html
名稱(chēng)欄目:sqlserver實(shí)現(xiàn)樹(shù)形結(jié)構(gòu)遞歸查詢(xún)(無(wú)限極分類(lèi))
文章網(wǎng)址:http://muchs.cn/article12/gesedc.html
成都網(wǎng)站建設(shè)公司_創(chuàng)新互聯(lián),為您提供做網(wǎng)站、網(wǎng)站制作、App開(kāi)發(fā)、網(wǎng)站策劃、響應(yīng)式網(wǎng)站、網(wǎng)站導(dǎo)航
聲明:本網(wǎng)站發(fā)布的內(nèi)容(圖片、視頻和文字)以用戶(hù)投稿、用戶(hù)轉(zhuǎn)載內(nèi)容為主,如果涉及侵權(quán)請(qǐng)盡快告知,我們將會(huì)在第一時(shí)間刪除。文章觀(guān)點(diǎn)不代表本網(wǎng)站立場(chǎng),如需處理請(qǐng)聯(lián)系客服。電話(huà):028-86922220;郵箱:631063699@qq.com。內(nèi)容未經(jīng)允許不得轉(zhuǎn)載,或轉(zhuǎn)載時(shí)需注明來(lái)源: 創(chuàng)新互聯(lián)