zoukankan      html  css  js  c++  java
  • Start with...Connect By子句的应用

    /*Start with...Connect By子句的应用*/

    /* 从树根往叶子递归 */
    select *
    from
    (
        select '1' as id, '10' as name,'0' as pid from dual union all
        select '2','11','1' from dual union all
        select '3','20','0' from dual union all
        select '4','12','1' from dual union all
        select '5','121','2' from dual    
    ) t
    start with t.pid = 0
    connect by prior id = t.pid;

    /* 执行结果 */

     1 10 0
     2 11 1
     5 121 2
     4 12 1
     3 20 0

    /* 从叶子往树根递归 */
    select *
    from
    (
        select '1' as id, '10' as name,'0' as pid from dual union all
        select '2','11','1' from dual union all
        select '3','20','0' from dual union all
        select '4','12','1' from dual union all
        select '5','121','2' from dual    
    ) t
    start with t.id = 5
    connect by prior pid = id;

    /* 执行结果 */

    5 121 2
    2 11 1
    1 10 0

    /* 显示各节点的路径 */

    select id, pid, name, substr(sys_connect_by_path(sort, '.'), 2) Path 
    from
    (
        select id, pid, name, row_number() over(partition by pid order by id) sort
        from
        (
            select '1' as id, '10' as name,'0' as pid from dual union all
            select '2','11','1' from dual union all
            select '3','20','0' from dual union all
            select '4','12','1' from dual union all
            select '5','121','2' from dual    
        ) t
    ) x
    start with pid = 0
    connect by prior id = pid;

    /* 执行结果 */

    1 0 10 1
    2 1 11 1.1
    5 2 121 1.1.1
    4 1 12 1.2
    3 0 20 2


     

  • 相关阅读:
    DECLARE
    deallocvt
    科研院所
    jQuery Ajax 确定 form 表单 submit 提交成功
    Java实现 LeetCode 10 正则表达式匹配
    Java实现 LeetCode 10 正则表达式匹配
    Java实现 LeetCode 9 回文数
    Java实现 LeetCode 9 回文数
    Java实现 LeetCode 9 回文数
    Java实现 LeetCode 8 字符串转换整数(atoi)
  • 原文地址:https://www.cnblogs.com/aspsmile/p/1407692.html
Copyright © 2011-2022 走看看