《SQL 进阶教程》 case:练习题1-1-1 多列数据的最大值
select name,
case when
case when x > y then x else y end < z then z
else case when x < y then y else x end
end as greaster
from greatests
select name,
case when
case when x > y then x else y end < z then z
else case when x < y then y else x end
end as greaster
from greatests