sql - update field value with multiple rows -

i have stored proc have temp table , need update value of "day_name" column. loop throug temp table , update value

this example of data(there multiple student names):

student        studentid    courseid    course_name           period    day_name bray, clifford  14088      10064    physical education 9gym     1         bray, clifford  14088      10064    physical education 9gym     1         b bray, clifford  14088      10064    physical education 9gym     1         c bray, clifford  14088      10064    physical education 9gym     1         d bray, clifford  14088      10064    physical education 9gym     2         bray, clifford  14088      10064    physical education 9gym     2         b bray, clifford  14088      10064    physical education 9gym     2         c bray, clifford  14088      10064    physical education 9gym     2         d bray, clifford  14088      10065    physical education 11gym    3         b bray, clifford  14088      10065    physical education 11gym    3         d bray, clifford  14088      10065    physical education 11gym    5         bray, clifford  14088      10065    physical education 11gym    5         c bray, clifford  14088      10065    physical education 11gym    6         bray, clifford  14088      10065    physical education 11gym    6         b bray, clifford  14088      10065    physical education 11gym    6         c bray, clifford  14088      10065    physical education 11gym    6         d bray, clifford  14088      10059    health 9p373                7         bray, clifford  14088      10059    health 9p373                7         b bray, clifford  14088      10059    health 9p373                7         c 

i data this:

student        studentid    courseid    course_name         period  day_name bray, clifford  14088      10064    physical education 9gym     1    abcd bray, clifford  14088      10064    physical education 9gym     2    abcd bray, clifford  14088      10065    physical education 11gym    3    bd bray, clifford  14088      10065    physical education 11gym    5    ac bray, clifford  14088      10065    physical education 11gym    6    abcd bray, clifford  14088      10059    health 9p373                7    abc 

thanks in advance:) please please help....

given have finite list of day names, easiest way explicit aggregation:

select student, studentid, courseid, course_name, period,        (max(case when day_name = 'a' day_name else '' end) +         max(case when day_name = 'b' day_name else '' end) +         max(case when day_name = 'c' day_name else '' end) +         max(case when day_name = 'd' day_name else '' end)        ) days         table t group student, studentid, courseid, course_name, period; 

if want table this, suggest create new table. modifying original 1 doesn't make sense -- have delete rows modifying or inserting values.