Sql中CASE语法的常见案例

Sql中CASE语法的常见案例

案例1：

1 case when field1 is null then field2
2         else field2end as 'field'

案例2：可用于统计

1 case when  field IS NOT NULL then 1 else 0 end as  qty

案例3：

1 case WHEN STATUS='NEW' then '状态1'
2         WHEN STATUS IN ('feild1', 'feild2') then '状态2'
3         WHEN STATUS in ('feild3','feild4')then '状态3'
4         WHEN STATUS IN ('feild5' ,'feild6') then '状态4'
5         WHEN STATUS IN('feild7','feild8' )then '状态5'
6         WHEN STATUS IN ('feild12') then '状态9'
7         WHEN STATUS IN('feild9' )then '状态6'
8         WHEN STATUS IN('feild10' )then '状态7' 
9         WHEN STATUS IN ('feild11') then '状态8' end AS STATUS,

 

posted @ 2020-05-20 11:21  小熊公子  阅读(391)  评论(0)    收藏  举报