// 使用Mybatis返回Map结构时字段别名需要用双引号包裹否则别名会全部大写或小写,
<select id="selectById" resultType = "map">
select id as "myId",name as "myName" from t_user
</select>
// 对象则不用
<select id="selectById" resultType = "xxx.User">
select id as myId,name as myName from t_user
</select>