mybatisPlus使用记录

1.mybatisplus多条件模糊查询时，代码写的都对，但是就是查询不到数据解决记录：

在数据源连接添加：&characterEncoding=utf-8

 

2.mybatisplus使用小例子：

①entity:（entity中有两个主键，使用@MppMultiId注解，要引入mybatisplus-plus依赖）

@Data
@TableName(value = "tag_region_ref")
public class TagRegionRef implements Serializable {

    private static final long serialVersionUID = 1L;

    @MppMultiId
    @TableField(value = "region_id")
    private String regionId;

    @MppMultiId
    @TableField(value = "tag_id")
    private String tagId;

}

②controller:

@GetMapping("/isBound")
public Result findById(@PathVariable("tagId") String tagId) {
    return Result.ok(handsetService.isBoundRegion(tagId));
}

③service:

public interface HandsetService extends IService<TagRegionRef> {
    boolean isBoundRegion(String tagId);
}

④Impl:

@Service
public class HandsetServiceImpl extends ServiceImpl<HandsetMapper, TagRegionRef> implements HandsetService {
    @Override
    public boolean isBoundRegion(String tagId) {
        return false;
    }
}

⑤mapper:

public interface HandsetMapper extends BaseMapper<TagRegionRef> {
}

⑥mapper.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.cars.ict.rbpsems.regionTag.mapper.HandsetMapper">
</mapper>

3.mybatisplus查询表里的全部数据：

userMapper.selectList(null);

 

4. 问题：Table 'keshe-lz.station_inf_rel_tree' doesn't exist

解决：在数据库表映射的实体类中添加@TableName(“表名”)

 

 

 

 

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