sql werve里 case when中是否可再嵌套case when?
例如有 代码 (dm)
100,101,102,...
select case when dm='100'then dm else case when dm<>'100' then dm end from ge
2013-05-20 10:24
2013-05-22 08:41
2013-05-23 08:00
2013-05-24 13:10