递归查找 children

Question

我有一个 table 这样的：

创建脚本：

CREATE #TableName TABLE (
    Id int, 
    Id_Group int, 
    Id_Menu int
)
INSERT INTO #TableName VALUES
(1, 20005, 1014),(2, 20003, 1054),(3, 20005, 1058),
(4, 20004, 1055),(5, 20004, 1056),(6, 20004, 1057),
(7, 20003, 1053),(8, 1014, 0),(9, 20003, 1014),
(10, 20003, 1052),(11, 20003, 1164),(12, 20003, 1065),
(13, 20003, 1066),(14, 20003, 1067),(15, 20003, 1068),
(16, 20004, 1014),(17, 50100, 20003),(18, 50200, 20003),
(19, 50100, 20004),(20, 50200, 20004),(21, 50100, 20005),
(22, 50200, 20005)

我得到 Id_Menu 例如 1014 它必须找到它的 id_menu 必须等于 1014 的记录，结果是 20003, 20004, 20005 并且对于结果list 我必须找到它的 id_menu 是 20003, 20004, 20005 等的所有记录

我该怎么做？

Answer 1

也许这个会有所帮助

; with CTE as(
select Id_Group from YourTable where Id_Menu=1014)
select c.Id_Group,y.Id_Menu from CTE c with(nolock) join YourTable y with(nolock) on c.Id_Group=y.Id_Group

Answer 2

递归 CTE 可以为您做事：

DECLARE @var int = 1014

;WITH rec AS (
SELECT  Id, 
        Id_Group, 
        Id_Menu,
        1 as [level]
FROM YourTable
WHERE Id_Group = @var
UNION ALL
SELECT  y.Id,
        y.Id_Group,
        y.Id_Menu,
        r.[level]+1
FROM YourTable y
INNER JOIN rec r
    ON r.Id_Group = y.Id_Menu
)

SELECT *
FROM rec

输出：

Id  Id_Group    Id_Menu level
8   1014        0       1
1   20005       1014    2
9   20003       1014    2
16  20004       1014    2
19  50100       20004   3
20  50200       20004   3
17  50100       20003   3
18  50200       20003   3
21  50100       20005   3
22  50200       20005   3

递归查找 children

Find children recursively

sql

tsql

sql-server

recursive-query