data

studentID	cID	studentRank	suggestedRank
459	5	1	1
459	25	2	3
459	3	3	2
459	7	4	11
459	20	NULL	4
459	19	NULL	5
459	4	NULL	6
459	2	NULL	7
459	14	NULL	8
459	8	NULL	9
459	18	NULL	10
459	6	NULL	12
459	9	NULL	13
459	15	NULL	14
459	1	NULL	15
459	10	NULL	16
459	17	NULL	17
459	16	NULL	18
459	21	NULL	19
459	24	NULL	20
459	13	NULL	21
459	22	NULL	22
459	23	NULL	23

gistfile1.txt

UPDATE dbo.StudentCategoryRankTable
SET studentRank = (
  CASE
    <cfloop>
    WHEN cID = clusterID THEN rank
    </cfloop>
    ELSE NULL END
)
WHERE studentID = @studentID
		AND occupationalCategoryID = 7