问题描述:
在使用如下代码进行查询时,报Error attempting to get column 'ID' from result set错误:
java
LambdaQueryWrapper<TimeFeature> wrapper = new LambdaQueryWrapper<>();
wrapper.eq(TimeFeature::getDate, currentDateTime);
TimeFeature timeFeature = timeFeatureMapper.selectOne(wrapper);
首先排除数据库字段大小写问题。
然后考虑ID字段在本轮逻辑中不是很重要,对代码做了如下更改,指定了查询字段:
java
LambdaQueryWrapper<TimeFeature> wrapper = new LambdaQueryWrapper<>();
wrapper.select(TimeFeature::getDate,TimeFeature::getDayType5)
.eq(TimeFeature::getDate, currentDateTime);
TimeFeature timeFeature = timeFeatureMapper.selectOne(wrapper);
结果查询正常,然后能得出结果集到实体类的映射过程出现问题。
然后通过排查代码,发现我的实体类使用了@AllArgsConstructor
注解,
java
@Data
@TableName("TIME_FEATURE")
@ApiModel(value = "TimeFeature对象", description = "日期类型映射")
@AllArgsConstructor
public class TimeFeature extends BaseEntity{
@ApiModelProperty("日期")
private LocalDateTime date;
@ApiModelProperty("类型")
private Integer dayType5;
}
这个注解导致了指定的默认构造方法是只包含date,dayType5两个参数的方法。所以无法通过默认的构造方法将对应的结果集映射到实体类。
所以将这个注解去掉就解决问题了。
引申思考,那使用@Builder
注解会不会导致类似的问题呢?