在T-SQL中以广度优先的方式进行深度优先遍历 [英] Getting depth-first traversal insted of breadth first in T-SQL

问题描述

我具有以下T-SQL功能: https://gist.github.com/cwattengard/11365802

I have the following T-SQL function: https://gist.github.com/cwattengard/11365802

这将以广度优先遍历返回数据.有没有简单的方法可以使此函数以深度优先遍历的方式返回其数据?我有一个Treeview组件可以满足这个要求(旧版系统).

This returns data in a breadth-first traversal. Is there a simple way to make this function return its data in a depth-first traversal? I have a treeview-component that excpects this (legacy system).

我已经有一个类似的存储过程，该存储过程以深度优先遍历的方式返回树，但它使用的是游标，而且速度很慢.(此功能需要6到7秒，而在同一数据上花费的时间不到一秒钟).

I already have a similar stored procedure that returns the tree in a depth-first traversal, but it's using cursors and is really slow. (6-7 seconds as opposed to this function that takes less than a second on the same data).

推荐答案

 http://sqlanywhere.blogspot.in/2012/10/example-recursive-union-tree-traversal.html

下面的图显示了树形表的主键:

Here's a diagram showing the primary keys for a tree-structured table:

                           1
                           |
       ---------------------------------------
       2            93            4          5       
       |             |            |          |
--------------  ------------  --------     ------  
6  7  8  9  10  11 12 13  14  15 16 17     18  19
   |                   |             |      |
 -----               -----         -----  -----
 27 26               25 24         23 22  21 20

以下是广度优先和深度优先查询应返回的内容:

Here's what the breadth-first and depth-first queries should return:

Breadth-First  Depth-First
1              1
2              2
93             6
4              7
5              27
6              26
7              8
8              9
9              10
10             93
11             11
12             12
13             13
14             25
15             24
16             14
17             4
18             15
19             16
27             17
26             23
25             22
24             5
23             18
22             21
21             20
20             19

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