请教各位大佬一个 mybatis plus 问题

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 select sum(JOIN_COUNT) as 'joinNum',sum(WIN_COUNT) as 'winNum',sum(DEFRAY_COUNT) as 'writeOffNum' from mkplat_activity_point where activity_id = #{activityId} and point_id >= #{start} and point_id <![CDATA[<]]> #{end}

请问这种 sql 在 mp 里面除了 xml 还有啥办法吗，selectMaps 有点麻烦，返回值还要把 map 转为对应的对象，能不能直接通过 mybatis plus 返回一个 StatisticsCount 出来

 @Override public StatisticsCount count(String activityId, String start, String end) { QueryWrapper<ActivityPointDO> wrapper = Wrappers.query(); wrapper.select("sum(JOIN_COUNT) as 'joinNum'","sum(WIN_COUNT) as 'winNum'","sum(DEFRAY_COUNT) as 'writeOffNum'"). eq("activity_id",activityId). ge("point_id",start). lt("point_id",end); List<Map<String, Object>> maps = this.getBaseMapper().selectMaps(wrapper); }

2 replies 2021-08-13 09:44:28 +08:00

hcen1997

Aug 12, 2021

在 mybatis 中, 如果 select 的列结果名和 class 的结果名对应上, 是可以直接转换的
<select> select a,b,c from tt where a = #{paramA} </select>
class CC { String a; String b; String c}
List<CC> getByParamA(@Param("paramA")String paramA);

上面这种 sql 和 class 对应的关系, 接口返回类型可以直接写类名, 自动转换了
mybatis 甚至可以自动转换驼峰和下划线

liian2019

Aug 13, 2021

@hcen1997 谢谢你，这个我知道，只是想用 mp 的方式，看看能不能脱离掉 xml