急求一解，关于加减的问题
table:score
字段 score id
77 1
66 2
55 3
8１ 4
score小于８０加５分 大于等于８０ 减５分

[解决办法]
select score = case when score <80 then score+5 else score-5 end, id from score
[解决办法]
update score set score = case when score < 80 then score + 5 else score - 5 end
[解决办法]
select score =(case when score <80 then score+5 else score-5 end), id from score
order by id