How to form Management Hierarchy Formation in SQL Server? - sql

Question

how to form the management hierarchy for below records?
Input Data:
Id
Sub ID
Name
Description
101
NULL
Page Reference
Page Reference
102
1
Page 1
Page 1
103
2
Ashok
Ashok
104
3
Kumar
Kumar
105
4
Page 2
Page 2
106
5
Arvind
Arvind
107
4
Page 11
Page 11
108
6
Gova
Gova
109
7
Gokul
Gokul
110
8
Kannan
Kannan
I tried with Recursion CTE, I am not able to find exact solution. Need an below format,
Conditions are
New Leaf ID --> If Sub ID IS NULL , then it will be 1 , If contains page row, it will be 2, if contains other than that it will be 3.
Page --> Whenever Page row starts, from the next row original information showing for that page. we need to form based on the lead rows.
Output Data:
Id
Sub ID
Name
Page
New Leaf ID
101
NULL
Page Reference
1
102
1
Page 1
Page 1
2
103
2
Ashok
Page 1
3
104
3
Kumar
Page 1
3
107
4
Page 11
Page 11
2
108
6
Gova
Page 11
3
109
7
Gokul
Page 11
3
110
8
Kannan
Page 11
3
105
4
Page 2
Page 2
2
106
5
Arvind
Page 2
3

Answer 1

The new leaf id is conditional logic. As for the page, it is a bit trickier: it seems like the ordering of the rows defines the dependencies, so basically you want to relate each level 3 leaf to the preceding level 2.
Here is an approach using a window count to identify leafs that belong to the same page:
select id, subid, name,
case when sub_id is not null
then max(case when name like 'Page %' then name end) over(order by id)
end as page,
case
when subid is null then 1
when name like 'Page %' then 2
else 3
end as new_leaf_id
from (
select t.*,
sum(case when name like 'Page %' then 1 else 0 end) over(order by id) grp
from mytable t
) t