在使用mybatis框架作查询的时候,出现了以下错误:java
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 's.areaname' in 'field list' at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_144] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_144]
在mapper.xml中写的sql:mysql
<select id="findList" parameterType="Advertisement" resultMap="AdvertisementResult"> SELECT a.id , a.title , a.img_path , a.url , a.description , a.sort , s.areaName , --注意这个字段 s1.short_name FROM advertisement a LEFT JOIN areas s ON a.province_id = s.id LEFT JOIN areas s1 on a.city_id = s1.id </select>
错误缘由:sql
在这里须要些sql代码,而不是实体中的驼峰命名。mybatis
解决思路:app
把areaName修改为area_name就能够了。框架