java hql case when的用法
if(null == sorter){ ???????????hql.append(" order by m.mDate desc,case when m.mealTime = ‘morning‘ then ‘1‘ when m.mealTime = ‘noon‘ then ‘2‘ when m.mealTime = ‘night‘ then ‘3‘ when m.mealTime = ‘midnight‘ then ‘4‘ end "); ???????}注：
上面hql语句的意思可以理解为：
通过mDate 降序排序，同时还得满足当mealTime = ‘morning‘ 时，在日期的基础上排第一位，当mealTime = ‘noon‘ 同理，以此类推即可。
case when既可以写在select后面，排序的时候也可以写在order by后面
下面是sql的case when写法
select t.id,t.name,t.code,t.select_time,t.now_level,case t.now_level WHEN ‘县处级正职领导职务‘ ?THEN 38 ?WHEN ‘县处级正职非领导职务‘ ?THEN 36 WHEN ‘县处级副职领导职务‘ ?THEN 34 ?WHEN ‘县处级副职非领导职务‘ ?THEN 31 WHEN ‘乡科级正职领导职务‘ ?THEN 28 WHEN ‘乡科级正职非领导职务‘ ?THEN 26 WHEN ‘乡科级副职非领导职务‘ ?THEN 21 WHEN ‘科员‘ ?THEN 20 WHEN ‘新录用未定级‘ ?THEN 19 WHEN ‘五级职员‘ ?THEN 18 WHEN ‘六级职员‘ ?THEN 15 WHEN ‘七级职员‘ ?THEN 13 WHEN ‘八级职员‘ ?THEN 11 WHEN ‘九级职员‘ ?THEN 9 WHEN ‘市管企业正职‘ ?THEN 6 WHEN ‘市管企业副职‘ ?THEN 3 WHEN ‘企事业其它‘ ?THEN 1 END leveFROM Torg_Cadre t WHERE ?t.status=2ORDER BY code desc,(date_format(select_time,‘%Y‘)) desc, leve desc;
多字段排序，每个字段后面都加desc或asc
关于hibernate中hql语句 case when的写法
原文地址：http://www.cnblogs.com/learnapi/p/7905272.html