奇偶数对换，当最后一位为奇数时不变

 变更之后 为

select id , 
if (id =(select max(id) from test_su) and (id % 2 != 0 ),id , if(id % 2 = 0 ,id -1 , id + 1))
,a from test_su
order by id 

 b

标签：奇偶,奇数,max,对换,su,test,id,select
来源： https://www.cnblogs.com/suheng01/p/15008082.html