Question

I have a tableA (ID int, Match varchar, tot int)

ID Match Tot
1  123
2  123
3  12
4  12
5  4
6  12
7  8

Now, I want to calculate Tot which is total number of match exists in the table. for example 123 occured twice, 12 exist thrice and so on. Also note that I want the count only at first match. here is the expected result.:

ID Match Tot
1  123    2
2  123
3  12     3
4  12
5  4      1
6  12
7  8      1

Another case:

    ID Match Count Tot
    1  123   2
    2  123   1
    3  12    10
    4  12    10
    5  4     3
    6  12    5
    7  8     7

Now I want to add the count for the same match. expected result:

    ID Match Count Tot
    1  123   2      3
    2  123   1
    3  12    10     25
    4  12    10
    5  4     3       3
    6  12    5  
    7  8     7       7

Thanks

Answer 1

WITH tableA(ID, Match) AS
(
SELECT 1,123 UNION ALL
SELECT 2,123 UNION ALL
SELECT 3,12 UNION ALL
SELECT 4,12 UNION ALL
SELECT 5,4 UNION ALL
SELECT 6,12 UNION ALL
SELECT 7,8
)
SELECT *,
       CASE
         WHEN ROW_NUMBER() OVER (PARTITION BY Match ORDER BY ID) = 1 
         THEN COUNT(*) OVER (PARTITION BY Match)
       END AS Tot
FROM   tableA
ORDER  BY ID