开发者

t-sql getting leaf nodes

开发者 https://www.devze.com 2022-12-30 13:34 出处:网络
Based on following table (I have kept spaces between the rows for clarity) Path ----------- \\node1\\node2\\node3

Based on following table (I have kept spaces between the rows for clarity)

Path
-----------
\node1\node2\node3
\node1\node2\node3\node5

\node1\node6\node3

\node1\node4\node3
\node1\node4\node3\node7
\node1\node4\node3\node8
\node1\node4\node3\node9
\node1\node4\node3\node9\node10

I want to get all the paths containing leaf node. So for instance, following will be considered leaf nodes for path \node1\node4\node3

\node1\node4\node3\node7
\node1\node4\node3\node8
\node1\node4\node3\node9\node10
开发者_开发技巧

The following will be the output:

Output
---------------------------
\node1\node2\node3\node5
\node1\node6\node3
\node1\node4\node3\node7
\node1\node4\node3\node8
\node1\node4\node3\node9\node10

Pls. suggest. Thanks.


You want to find all the leaves, which are all the paths which aren't contained in any other paths. You can do this by checking for each path whether there is another path that contains it, as follows:

SELECT Path FROM Table1 T1
WHERE NOT EXISTS (
    SELECT NULL
    FROM Table1 T2
    WHERE T2.Path LIKE T1.Path + '\%'
)

Results:

Path
\node1\node2\node3\node5
\node1\node6\node3
\node1\node4\node3\node7
\node1\node4\node3\node8
\node1\node4\node3\node9\node10


A like clause would appear to do the trick:

select Path
from YourTable
where Path like '%\node3\%'
or Path like '%\node3'
or Path like 'node3\%'
0

精彩评论

暂无评论...
验证码 换一张
取 消