mybatis映射查询一对多，多对一

CREATE TABLE "public"."yj_advice" (
  "uuid" varchar(255) COLLATE "pg_catalog"."default" NOT NULL,
  "title" varchar(255) COLLATE "pg_catalog"."default",
  "type" varchar(10) COLLATE "pg_catalog"."default",
  "content" text COLLATE "pg_catalog"."default",
  "applicant" varchar(255) COLLATE "pg_catalog"."default",
  "status" varchar(20) COLLATE "pg_catalog"."default",
  "create_time" varchar(50) COLLATE "pg_catalog"."default",
  "update_time" varchar(50) COLLATE "pg_catalog"."default"
)
;
COMMENT ON COLUMN "public"."yj_advice"."title" IS '标题';
COMMENT ON COLUMN "public"."yj_advice"."type" IS '类型';
COMMENT ON COLUMN "public"."yj_advice"."content" IS '意见内容';
COMMENT ON COLUMN "public"."yj_advice"."applicant" IS '申请人';
COMMENT ON COLUMN "public"."yj_advice"."status" IS '状态';
COMMENT ON COLUMN "public"."yj_advice"."create_time" IS '创建时间';
COMMENT ON COLUMN "public"."yj_advice"."update_time" IS '更新时间';

-- ----------------------------
-- Records of yj_advice
-- ----------------------------
INSERT INTO "public"."yj_advice" VALUES ('fa91ae681b8a4153a3ca7cee2da6a073', 'test', '系统bug', '111', '超级管理员', '未解决', '2022-01-07 14:51:51.0', '2022-01-07 14:51:51.0');
INSERT INTO "public"."yj_advice" VALUES ('d5806338df89491995c046bf33aa82c7', '231', '数据问题', '23', '超级管理员', '未解决', '2022-01-07 14:52:04.0', '2022-01-07 14:52:04.0');
INSERT INTO "public"."yj_advice" VALUES ('64eedecea44449bf84db00b344e97c33', '111', '系统bug', '23', '超级管理员', '未解决', '2022-01-07 14:53:25.0', '2022-01-07 14:53:25.0');
INSERT INTO "public"."yj_advice" VALUES ('64312d170032496992f1ffba406c2296', '1222', '数据问题', '1', '超级管理员', '未解决', '2022-01-07 15:16:19.0', '2022-01-07 15:16:19.0');
INSERT INTO "public"."yj_advice" VALUES ('4cd5ab5b97b24c4083233df5c600fd73', '曹猛测试', '数据问题', '222', '超级管理员', '未解决', '2022-01-07 15:18:12.0', '2022-01-07 15:18:12.0');
INSERT INTO "public"."yj_advice" VALUES ('150dd7a0487d453ca0435bafe4426c12', '测试改22223', '系统bug改', '测试修改', '超级管理员', '未解决', '2021-12-31 09:56:07.0', '2022-01-07 15:21:01.0');

CREATE TABLE "public"."yj_advice_attach" (
  "uuid" varchar(255) COLLATE "pg_catalog"."default" NOT NULL,
  "ad_uuid" varchar(255) COLLATE "pg_catalog"."default",
  "path" text COLLATE "pg_catalog"."default",
  "create_time" varchar(50) COLLATE "pg_catalog"."default"
)
;
COMMENT ON COLUMN "public"."yj_advice_attach"."ad_uuid" IS '反馈意见id';
COMMENT ON COLUMN "public"."yj_advice_attach"."path" IS '路径';
COMMENT ON COLUMN "public"."yj_advice_attach"."create_time" IS '创建时间';

-- ----------------------------
-- Records of yj_advice_attach
-- ----------------------------
INSERT INTO "public"."yj_advice_attach" VALUES ('07c3fa6df5784e32a7fcdccd42fc38a7', '150dd7a0487d453ca0435bafe4426c12', 'adviceFile/150dd7a0487d453ca0435bafe4426c12/07c3fa6df5784e32a7fcdccd42fc38a7/震惊.jpg', '2021-12-31 10:08:05.0');
INSERT INTO "public"."yj_advice_attach" VALUES ('fe23ee821a3a411aa6653505caeb23c1', '150dd7a0487d453ca0435bafe4426c12', 'adviceFile/150dd7a0487d453ca0435bafe4426c12/fe23ee821a3a411aa6653505caeb23c1/震惊①.jpg', '2021-12-31 10:08:05.0');
INSERT INTO "public"."yj_advice_attach" VALUES ('171c37181da84333bed8367d9387c0f9', '64312d170032496992f1ffba406c2296', 'adviceFile/64312d170032496992f1ffba406c2296/171c37181da84333bed8367d9387c0f9/污水 (1).png', '2022-01-07 15:16:20.0');
INSERT INTO "public"."yj_advice_attach" VALUES ('4855adff9bec4104b243535c87732368', '4cd5ab5b97b24c4083233df5c600fd73', 'adviceFile/4cd5ab5b97b24c4083233df5c600fd73/4855adff9bec4104b243535c87732368/3.jpg', '2022-01-07 15:18:12.0');

-- ----------------------------
-- Primary Key structure for table yj_advice
-- ----------------------------
ALTER TABLE "public"."yj_advice" ADD ConSTRAINT "feedback_pkey" PRIMARY KEY ("uuid");

-- ----------------------------
-- Primary Key structure for table yj_advice_attach
-- ----------------------------
ALTER TABLE "public"."yj_advice_attach" ADD ConSTRAINT "feedback_attach_pkey" PRIMARY KEY ("uuid");

实体类

@Data
public class YjAdvice {
    private String uuid;
    private String title;
    private String type;
    private String content;
    private String applicant;
    private String status;
    private String createTime;
    private String updateTime;
    // 意见附件集合
    @TableField(select = false)
    private List attachList;
}

mapper

@Mapper
public interface YjAdviceMapper {
    List getYjByUUID(@Param("uuid") String uuid);
}

mapper.xml

  
  
    
    
    
    
    
    
    
    
    
    
    
    
       
      
      
      
    
  

  
    select t1.*,t2.uuid attuuid,t2.path,t2.ad_uuid from yj_advice t1 left join yj_advice_attach t2 on t1.uuid=t2.ad_uuid
    
      
        and t2.ad_uuid=#{uuid}
      
    
  


 
 
 
测试结果
 
 
@RestController
@RequestMapping("onetomany")
public class oneToManyController {
 	@Autowired
    private YjAdviceMapper yjAdviceMapper;
    
    @GetMapping
    public List getYj(String uuid){
        List yjByUUID = yjAdviceMapper.getYjByUUID(uuid);
        return yjByUUID;
    }
}
 
 
多对一 
 
 
实体类
 
 
@Data
public class YjAdviceAttach {
    private String uuid;
    private String adUuid;
    private String path;
    
    @TableField(select = false)
    private YjAdvice yjAdvice;
}
 
 
 
mapper
 
 
@Mapper
public interface YjAdviceAttachMapper {

    List listYjAttach(String uuid);
}
 
 
 
mapper.xml
 
 




 
  
    
    
    
    
    
    
      
        
        
        
        
        
        
    
  
  
    SELECT t1.*,t2.uuid yjuuid,t2.title,t2."type",t2.status,t2."content",t2.applicant FROM "yj_advice_attach" t1,yj_advice t2
    
      and t1.ad_uuid=t2.uuid
      
        and t1.uuid=#{uuid}
      
    
  

测试结果

@RestController
@RequestMapping("onetomany")
public class oneToManyController {

    @Autowired
    private YjAdviceMapper yjAdviceMapper;
    @Autowired
    private YjAdviceAttachMapper yjAdviceAttachMapper;

    
    @GetMapping
    public List getYj(String uuid){
        List yjByUUID = yjAdviceMapper.getYjByUUID(uuid);
        return yjByUUID;
    }

    
    @GetMapping("getYjAttach")
    public List getYjAttach(String uuid){
        List yjAdviceAttaches = yjAdviceAttachMapper.listYjAttach(uuid);
        return yjAdviceAttaches;
    }
}