mybatis 如果是varchar 类型 ,字段值为空时,会显示“null”
<select id="getDXDetail" resultType="java.util.HashMap" parameterType="map">
select a.xm as dxxm ,
a.xydm as dxxydm ,a.zzjgdm as dxzzjgdm ,
b.zxwbsj as ajzxwbsj
from cj_gs_dx a ,cj_gs_aj b
where
a.ajunid=b.unid
and ajunid = (select ajunid from cj_gs_dx where unid ='330201132016072100000027')
order by dxxm
</select>
当查询结果为空的时候,java后台获取不到该字段,该结果为null、如何解决