SQL Server 2008 R2: Recursive query - sql-server

Question

This is the follow up question of : Prepare a recursive query
I have the table with the two columns namely cola and colb as shown below:
Table : Test
create table Test
(
cola int,
colb int
);
Records I have entered are:
Cola Colb
------------
1 2
1 3
1 4
2 5
2 6
2 3
3 2
3 4
3 7
3 10
10 11
11 12
11 13
11 14
12 15
13 16
14 99
15 88
16 77
Note: Now I want to show the only records who are connected with value I have pass. For example If I pass the value as 1 then it should display me the connected number to it and form connect like a tree.
For the above requirement I have got the script from Dark Knight as shown below which works fine.
;WITH CTE AS
(
SELECT COLA,COLB,','+CAST(COLA AS VARCHAR(MAX))+',' AS CHCK FROM test WHERE COLA=1
UNION ALL
SELECT C1.COLA,C1.COLB,C.CHCK+CAST(C1.cola AS VARCHAR(MAX))+','
FROM CTE C INNER JOIN test C1 ON C.colb = C1.cola
WHERE CHARINDEX(','+CAST(C.colb AS VARCHAR(MAX))+',',C.CHCK)=0
),
OUTERCTE AS
(
SELECT DISTINCT COLA,COLB,ROW_NUMBER() OVER(PARTITION BY Colb ORDER BY Cola) rn FROM CTE --ORDER BY COLA
)
SELECT Cola,Colb FROM OUTERCTE
WHERE rn<=1
ORDER BY CASE WHEN Cola = 1 THEN 1 ELSE 2 END;
Which gives me this:
----------------
Cola Colb
----------------
1 2
1 3
1 4
2 5
2 6
3 7
3 10
10 11
11 12
11 13
11 14
12 15
13 16
16 77
15 88
14 99
Requirement: Now I want to show the levels of records.
Expected Result:
------------------------------
Cola Colb Level
------------------------------
1 2 1
1 3 1
1 4 1
2 5 2
2 6 2
3 7 2
3 10 2
10 11 3
11 12 4
11 13 4
11 14 4
12 15 5
13 16 5
16 77 6
15 88 6
14 99 5

Answer 1

;WITH CTE AS
(
SELECT COLA,COLB
,','+CAST(COLA AS VARCHAR(MAX))+',' AS CHCK
, 1 as lvl FROM #Test WHERE COLA=1
UNION ALL
SELECT C1.COLA,C1.COLB ,C.CHCK+CAST(C1.cola AS VARCHAR(MAX))+','
, c.lvl+1
FROM CTE C INNER JOIN #Test C1 ON C.colb = C1.cola
WHERE CHARINDEX(','+CAST(C.colb AS VARCHAR(MAX))+',',C.CHCK)=0
),
cte2 as (
select * , ROW_NUMBER() over (partition by colb order by lvl)as rn From CTE
)
select cola,colb,lvl from cte2 where rn = 1