SQL join unexpected result

[Jolied]

I have the following table:

item	running	resourceid
017510	C1	43
338877	C4	44
451233	C1	45
771225	C4	41
011212	C4	47
313366	C3	34
771226	C4	48
990000	C4	46

for each "running" I need to get the Max resourceid and it's item which give me the expected result:

running	resourceid	item
C1	45	451233
C3	34	313366
C4	48	771226

With this code:

SELECT
b.running,
MAX(b.resourceid)as MaxResourceid,
MAX(b.item) as item
FROM runningResources as b
inner join (SELECT 
    running,
    MAX(resourceid) as MaxValue
    FROM runningResources
    GROUP BY running ) a ON
    a.running=b.running and a.Maxvalue=b.resourceid
    group by b.running

Since the query

SELECT
b.running,
MAX(b.resourceid)as MaxResourceid,
MAX(b.item) as item
FROM runningResources as b
group by b.running

gives the result:

running	resourceid	item
C1	45	451233
C3	34	313366
C4	48	990000

why is C4 in the final result showing 771226 ? I would think that the join would give the item of the outer SELECT (C4,48,990000)

[briley]

use row_number() to find the row with the highest resourceid. And then filter it at the outer query

select running, resourceid, item
from   ( 
           select *, rn = row_number() over (partition by running 
                                                 order by resourceid desc)
           from   runningResources 
       ) as a
where  a.rn = 1