出现以下错误,多次检查sql语句并没有错,错误的中文翻译是:期望由selectOne()返回一个结果(或null),但是找到:24
我的mapper代码如下:
//更改前
public CarInfo findCarInfo(@Param("car_id")String carid,@Param("car_num")String carnum);
对应的sql语句;
<!-- 动态sql -->
<select id="findCarInfo" resultType="CarInfo">
select * from car_info where 1=1
<choose>
<when test="car_id != null and car_num != ''">
and car_id = #{car_id}
</when>
<when test="car_num != null and car_num != ''">
and car_num like concat('%',#{car_num},'%')
</when>
<otherwise>
and car_id is not null
</otherwise>
</choose>
</select>
错误的原因是当sql返回了多条数据,mapper中,返回就不能使用类CatInfo了,这里更改为List集合,更改后mapper代码如下:
// 更改后
public List<CarInfo> findCarInfo(@Param("car_id")String carid,@Param("car_num")String carnum);
以上错误就成功解决了,希望能帮到大家,谢谢