Mybatis-Plus用纯注解完成一对多&多对多查询
石苏燕
Mybatis-Plus用纯注解搞定一对多&多对多查询
业务中很常见的用户-角色就属于典型的多对多关系. 假设我们需要将用户信息（包括了用户对应的角色信息）查询出来
多对多
数据表结构
user表和role表的关系为多对多，即一个user可以分配多个role，一个role可以属于多个user。
1.user表
CREATE TABLE `user` (
`id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键',
`nickname` varchar(20) NOT NULL COMMENT '昵称',
`birthday` date NOT NULL COMMENT '生日',
`username` varchar(32) NOT NULL COMMENT '用户名',
`password` varchar(30) NOT NULL COMMENT '密码',
`status` varchar(2) NOT NULL DEFAULT '0' COMMENT '状态 ',
`create_time` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
`update_time` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
PRIMARY KEY (`id`) USING BTREE
) ENGINE=InnoDB;
INSERT INTO `user` VALUES (1, 'lh', '2022-06-29', '李大', '123456', '0', '2022-06-29 09:02:07', '2022-06-29 09:02:07');
INSERT INTO `user` VALUES (2, 'ww', '2022-06-29', '陈大', '123456', '0', '2022-06-29 13:06:24', '2022-06-29 13:06:24');
INSERT INTO `user` VALUES (3, 'aa', '2022-06-29', '刘达', '123456', '0', '2022-06-29 13:06:48', '2022-06-29 13:06:48');
2.role表
CREATE TABLE `role` (
`id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键id',
`name` varchar(20) NOT NULL COMMENT '角色名称',
`remark` varchar(50) DEFAULT NULL COMMENT '角色描述',
PRIMARY KEY (`id`) USING BTREE
) ENGINE=InnoDB;
INSERT INTO `role` VALUES (1, '系统管理员', '系统管理员');
INSERT INTO `role` VALUES (2, '数据管理员', '数据管理员');
3.user_role中间表
CREATE TABLE `user_role` (
`user_id` int(11) NOT NULL COMMENT '用户id',
`role_id` int(11) DEFAULT NULL COMMENT '角色id'
) ENGINE=InnoDB;
INSERT INTO `user_role` VALUES (1, 1);
INSERT INTO `user_role` VALUES (1, 2);
INSERT INTO `user_role` VALUES (2, 1);
INSERT INTO `user_role` VALUES (2, 2);
INSERT INTO `user_role` VALUES (3, 1);
实体类:
1.User类:
package wjw.test.mybatisplus.vo;
import java.io.Serializable;
import java.time.LocalDate;
import java.time.LocalDateTime;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
public class User implements Serializable {
private static final long serialVersionUID = 1L;
@TableId(
type = IdType.AUTO)
/**
* 主键
*/
private Integer id;
/**
* 昵称
*/
private String nickname;
/**
* 生日
*/
private LocalDate birthday;
/**
* 用户名
*/
private String username;
/**
* 密码
*/
private String password;
/**
* 状态
*/
private String status;
/**
* 创建时间
*/
private LocalDateTime createTime;
/**
* 更新时间
*/
private LocalDateTime updateTime;
public User() {
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getNickname() {
return nickname;
}
public void setNickname(String nickname) {
this.nickname = nickname;
}
public LocalDate getBirthday() {
return birthday;
}
public void setBirthday(LocalDate birthday) {
this.birthday = birthday;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
public LocalDateTime getCreateTime() {
return createTime;
}
public void setCreateTime(LocalDateTime createTime) {
this.createTime = createTime;
}
public LocalDateTime getUpdateTime() {
return updateTime;
}
public void setUpdateTime(LocalDateTime updateTime) {
this.updateTime = updateTime;
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("User [id=");
builder.append(id);
builder.append(", nickname=");
builder.append(nickname);
builder.append(", birthday=");
builder.append(birthday);
builder.append(", username=");
builder.append(username);
builder.append(", password=");
builder.append(password);
builder.append(", status=");
builder.append(status);
builder.append(", createTime=");
builder.append(createTime);
builder.append(", updateTime=");
builder.append(updateTime);
builder.append("]");
return builder.toString();
}
}
2.Role类:
package wjw.test.mybatisplus.vo;
import java.io.Serializable;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
public class Role implements Serializable {
private static final long serialVersionUID = 1L;
@TableId(
type = IdType.AUTO)
/**
* 主键id
*/
private Integer id;
/**
* 角色名称
*/
private String name;
/**
* 角色描述
*/
private String remark;
public Role() {
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRemark() {
return remark;
}
public void setRemark(String remark) {
this.remark = remark;
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("Role [id=");
builder.append(id);
builder.append(", name=");
builder.append(name);
builder.append(", remark=");
builder.append(remark);
builder.append("]");
return builder.toString();
}
}
3.包含一对多关系的UserVo类:
package wjw.test.mybatisplus.vo;
import java.time.LocalDate;
import java.util.List;
public class UserVo {
/**
* 用户编号
*/
private Integer id;
/**
* 昵称
*/
private String nick_Name;
/**
* 用户名
*/
private String username;
/**
* 生日
*/
private LocalDate birthday;
private List<Role> roles;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getNick_Name() {
return nick_Name;
}
public void setNick_Name(String nick_Name) {
this.nick_Name = nick_Name;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public LocalDate getBirthday() {
return birthday;
}
public void setBirthday(LocalDate birthday) {
this.birthday = birthday;
}
public List<Role> getRoles() {
return roles;
}
public void setRoles(List<Role> roles) {
this.roles = roles;
}
public UserVo() {
super();
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("UserVo [id=");
builder.append(id);
builder.append(", nick_Name=");
builder.append(nick_Name);
builder.append(", username=");
builder.append(username);
builder.append(", birthday=");
builder.append(birthday);
builder.append(", roles=");
builder.append(roles);
builder.append("]");
return builder.toString();
}
}
Mapper类:
1.RoleMapper:
package wjw.test.mybatisplus.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import wjw.test.mybatisplus.vo.Role;
@Mapper
public interface RoleMapper extends BaseMapper<Role> {
/**
* 根据指定的userId去user和user_role关联表查出该user所属role列表
* @param userId
* @return
*/
@Select("select * from role left join user_role on role.id=user_role.role_id where user_role.user_id=#{userId}")
List<Role> getListByUserId(Integer userId);
}
2.UserMapper:
package wjw.test.mybatisplus.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Many;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import wjw.test.mybatisplus.vo.User;
import wjw.test.mybatisplus.vo.UserVo;
@Mapper
public interface UserMapper extends BaseMapper<User> {
//OneToMany一对多查询
@Select("select * from user where ${ew.sqlSegment}")
@Results({@Result(column = "id",property = "id"), // <1>
@Result(column = "nickname",property = "nick_Name"),
@Result(column = "id" /* 这里的id是要传递给下面查询里需要的参数 */, //<2>
property = "roles" /* 这里是UserVo类里的roles字段 */,many=@Many(
select = "wjw.test.mybatisplus.mapper.RoleMapper.getListByUserId"
))
})
List<UserVo> getList(@Param("ew") QueryWrapper wrapper);
}
<1>:
@Result(column=“id”,property=“Id”),这个可以不写，也不会报错，但是会导致我们查询结果列表里每个UVO 实体的Id等属性没有值。<2>: 这个@Result中
column, 主表中的列名，这个列的值要作为查询参数传给子查询。
property，代表子查询的查询结果关联的实体属性，就是UserVo中的roles字段。
select="wjw.test.mybatisplus.mapper.RoleMapper.getListByUserId"代表使用的子查询方法，就是RoleMapper类里的getListByUserId()方法。 意思就是查询主表，并将主表的id这个列和子查询关联起来，将id的值作为查询条件传入子查询中，子查询返回的结果存入到属性roles中.
测试
package wjw.test.mybatisplus;
import java.util.List;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
import org.springframework.test.context.ActiveProfiles;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import wjw.test.mybatisplus.mapper.RoleMapper;
import wjw.test.mybatisplus.mapper.UserMapper;
import wjw.test.mybatisplus.vo.User;
import wjw.test.mybatisplus.vo.UserVo;
@SpringBootTest(webEnvironment = WebEnvironment.NONE)
public class MybatisPlusTests1 {
@Autowired
private UserMapper userMapper;
public MybatisPlusTests1() {
//
}
@BeforeEach
public void setup() {
//
}
@AfterEach
public void stop() {
}
@Test
public void getUserInfo(){
QueryWrapper<User> wrapper=new QueryWrapper();
wrapper.in("id",1,2);
List<UserVo> list = userMapper.getList(wrapper);
System.out.println(list);
}
}
输出结果:
wjw.test.mybatisplus.MybatisPlusTests1 - [logStarted,61] - Started MybatisPlusTests1 in 2.855 seconds (JVM running for 3.885)
wjw.test.mybatisplus.mapper.UserMapper.getList - [debug,137] - ==> Preparing: select * from user where (id IN (?,?))
wjw.test.mybatisplus.mapper.UserMapper.getList - [debug,137] - ==> Parameters: 1(Integer), 2(Integer)
wjw.test.mybatisplus.mapper.UserMapper.getList - [trace,143] - <== Columns: id, nickname, birthday, username, password, status, create_time, update_time
wjw.test.mybatisplus.mapper.UserMapper.getList - [trace,143] - <== Row: 1, lh, 2022-06-29, 李大, 123456, 0, 2022-06-29 09:02:07.0, 2022-06-29 09:02:07.0
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [debug,137] - ====> Preparing: select * from role left join user_role on role.id=user_role.role_id where user_role.user_id=?
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [debug,137] - ====> Parameters: 1(Integer)
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [trace,143] - <==== Columns: id, name, remark, user_id, role_id
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [trace,143] - <==== Row: 1, 系统管理员, 系统管理员, 1, 1
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [trace,143] - <==== Row: 2, 数据管理员, 数据管理员, 1, 2
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [debug,137] - <==== Total: 2
wjw.test.mybatisplus.mapper.UserMapper.getList - [trace,143] - <== Row: 2, ww, 2022-06-29, 陈大, 123456, 0, 2022-06-29 13:06:24.0, 2022-06-29 13:06:24.0
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [debug,137] - ====> Preparing: select * from role left join user_role on role.id=user_role.role_id where user_role.user_id=?
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [debug,137] - ====> Parameters: 2(Integer)
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [trace,143] - <==== Columns: id, name, remark, user_id, role_id
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [trace,143] - <==== Row: 1, 系统管理员, 系统管理员, 2, 1
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [trace,143] - <==== Row: 2, 数据管理员, 数据管理员, 2, 2
w.t.mybatisplus.mapper.RoleMapper.getListByUserId - [debug,137] - <==== Total: 2
wjw.test.mybatisplus.mapper.UserMapper.getList - [debug,137] - <== Total: 2
[UserVo [id=1, nick_Name=lh, username=李大, birthday=2022-06-29, roles=[Role [id=1, name=系统管理员, remark=系统管理员], Role [id=2, name=数据管理员, remark=数据管理员]]], UserVo [id=2, nick_Name=ww, username=陈大, birthday=2022-06-29, roles=[Role [id=1, name=系统管理员, remark=系统管理员], Role [id=2, name=数据管理员, remark=数据管理员]]]]
将user的id=1,id=2传入，得到结果如下：
[UserVo [id=1, nick_Name=lh, username=李大, birthday=2022-06-29, roles=[Role [id=1, name=系统管理员, remark=系统管理员], Role [id=2, name=数据管理员, remark=数据管理员]]], UserVo [id=2, nick_Name=ww, username=陈大, birthday=2022-06-29, roles=[Role [id=1, name=系统管理员, remark=系统管理员], Role [id=2, name=数据管理员, remark=数据管理员]]]]
可以看出表中id为1和2的user信息和其对应的角色信息都已经查询出来了。
如果传递多个参数呢?
如果select属性指定的方法需要多个参数,column的写法是这样的:column = "{查询参数1=主查询列名1, 查询参数2=主查询列名2}"
@Select({"select * from group where account_id=#{accountId} and delete_flag=0"})
@Results({@Result(property = "groupId", column = "group_id", id = true),
@Result(property = "name", column = "user_name"),
@Result(property = "accountId", column = "account_id"),
@Result(property = "deleteFlag", column = "delete_Flag"),
@Result(property = "parentId", column = "parent_Id"),
@Result(property = "userList", many
//"groupId=group_id",相当于将主查询中的列group_id映射到查询参数groupId中
//"userName=user_name",相当于将主查询中的列user_name映射到查询参数userName中
=@Many(select="selectUsersByGroupId"), column = "{groupId=group_id ,userName=user_name}")})
List<Group> selectGroupWithUsers(@Param("accountId") String accountId);
@Select({"select u.* from user u",
"inner join user_group ug on u.user_id = ug.user_id",
"where ug.group_id=#{groupId} and u.user_name=#{userName} and u.delete_flag=0"
})
List<User> selectUsersByGroupId(@Param("groupId") String groupId, @Param("userName") String userName);
一对多
再实战一个不用中间表的一对多的例子
数据表结构
1.主表(bfs_nota1001)
CREATE TABLE `bfs_nota1001` (
`id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '与业务无关的自增主键',
`f_notaunikey` char(32) NOT NULL COMMENT '标识一条记录的key,由业务字段的MD5成的32个字节的字符串',
`f_head` char(12) NOT NULL COMMENT '报文头,长度(字节): 12',
`f_msgtype` varchar(100) NOT NULL COMMENT '消息类型,',
`f_drivercode` char(9) NOT NULL COMMENT '设备编号,长度(字节): 9',
`f_qr_cdrivercode` varchar(9) NOT NULL COMMENT 'QR设备编号,长度(字节): 9',
`f_qr_fdatetime` timestamp NOT NULL COMMENT 'QR封包时间',
`f_qr_randomnum` char(5) NOT NULL COMMENT 'QR钞捆序号,长度(字节): 5',
PRIMARY KEY (`id`),
UNIQUE KEY `bfs_nota1001_un` (`f_notaunikey`)
);
INSERT INTO `bfs_nota1001` VALUES (1,'3c496a9cac5986b5e9dc876f4f0401ff','GDAP20200527','1001','M02000930','M02000429','2020-05-27 09:28:39','20022');
2.子表(bfs_nota1001_detail)
CREATE TABLE `bfs_nota1001_detail` (
`id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '与业务无关的自增主键',
`f_notaunikey` char(32) NOT NULL COMMENT '标识一条记录的key,由相关的表bfs_nota1001的字段f_notaunikey来赋值',
`f_detailunikey` char(32) NOT NULL COMMENT '标识一条记录的key,由业务字段的MD5成的32个字节的字符串',
`f_moneyslogan` char(2) NOT NULL COMMENT '钞口号,长度(字节): 2',
`f_keynum` char(5) NOT NULL COMMENT '把号,长度(字节): 5',
`f_backcode` char(5) NOT NULL COMMENT '银行缩写,长度(字节): 5',
`f_detailbacksx` char(9) NOT NULL COMMENT '银行代码,长度(字节): 9',
`f_drvercode` char(9) NOT NULL COMMENT '设备编号,长度(字节): 9',
`f_btime` timestamp NOT NULL COMMENT '时间,长度(字节): 12',
`f_coupons` char(3) NOT NULL COMMENT '券别,长度(字节): 3',
`f_couponcount` int(11) NOT NULL COMMENT '张数,长度(字节): 4',
`f_couponvalue` int(11) NOT NULL COMMENT '金额,长度(字节): 6',
`f_revision` varchar(10) NOT NULL COMMENT '版本,长度(字节): 10',
PRIMARY KEY (`id`),
UNIQUE KEY `bfs_nota1001_detail_un` (`f_detailunikey`),
KEY `bfs_nota1001_detail_key` (`f_notaunikey`)
);
INSERT INTO `bfs_nota1001_detail` VALUES (1,'3c496a9cac5986b5e9dc876f4f0401ff','e5d73440e633b7783eb3fb957ae60e3','02','00019','51000','771600110','M02000429','2020-05-27 09:27:49','100',100,10000,'2015FIT '),(2,'3c496a9cac5986b5e9dc876f4f0401ff','ad2a34af3038a87f263b8f9ea771e4f1','02','00016','51000','771600110','M02000429','2020-05-27 09:27:51','100',100,10000,'2015FIT '),(3,'3c496a9cac5986b5e9dc876f4f0401ff','75a42347de99ece9d706dbb7c804ca0d','02','00018','51000','771600110','M02000429','2020-05-27 09:27:54','100',100,10000,'2015FIT '),(4,'3c496a9cac5986b5e9dc876f4f0401ff','92e78b01edb6e03f3746c284e80ebc73','02','00014','51000','771600110','M02000429','2020-05-27 09:27:56','100',100,10000,'2015FIT '),(5,'3c496a9cac5986b5e9dc876f4f0401ff','b95e2e493947c5f522546b6fa4d3ba3d','01','00022','51000','771600110','M02000429','2020-05-27 09:27:59','100',100,10000,'2015FIT '),(6,'3c496a9cac5986b5e9dc876f4f0401ff','a5efae152a9da726807e5c9a743c1b6d','01','00025','51000','771600110','M02000429','2020-05-27 09:28:01','100',100,10000,'2015FIT '),(7,'3c496a9cac5986b5e9dc876f4f0401ff','68cb897a34180f92a606aa5a73f20a0b','02','00015','51000','771600110','M02000429','2020-05-27 09:28:04','100',100,10000,'2015FIT '),(8,'3c496a9cac5986b5e9dc876f4f0401ff','24ffd138d550e59243b1c65504c24d6a','01','00017','51000','771600110','M02000429','2020-05-27 09:28:06','100',100,10000,'2015FIT '),(9,'3c496a9cac5986b5e9dc876f4f0401ff','ff9b18003d7f730a77deabeba6fd453d','02','00012','51000','771600110','M02000429','2020-05-27 09:28:09','100',100,10000,'2015FIT '),(10,'3c496a9cac5986b5e9dc876f4f0401ff','c9ab32450ec9154b84b3ad98918030e2','01','00024','51000','771600110','M02000429','2020-05-27 09:28:12','100',100,10000,'2015FIT ');
实体类:
1.主类(BfsNota1001)
package wjw.test.mybatisplus.slave.vo;
import java.io.Serializable;
import java.time.LocalDateTime;
import java.util.List;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
public class BfsNota1001 implements Serializable {
private static final long serialVersionUID = 1L;
@TableId(
type = IdType.AUTO)
/**
* 与业务无关的自增主键
*/
private Long id;
/**
* 标识一条记录的key，由业务字段的md5成的32个字节的字符串
*/
private String fNotaunikey;
/**
* 报文头，长度(字节)
*/
private String fHead;
/**
* 消息类型，
*/
private String fMsgtype;
/**
* 设备编号，长度(字节)
*/
private String fDrivercode;
/**
* qr设备编号，长度(字节)
*/
private String fQrCdrivercode;
/**
* qr封包时间
*/
private LocalDateTime fQrFdatetime;
/**
* qr钞捆序号，长度(字节)
*/
private String fQrRandomnum;
private List<BfsNota1001Detail> details;
public BfsNota1001() {
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getfNotaunikey() {
return fNotaunikey;
}
public void setfNotaunikey(String fNotaunikey) {
this.fNotaunikey = fNotaunikey;
}
public String getfHead() {
return fHead;
}
public void setfHead(String fHead) {
this.fHead = fHead;
}
public String getfMsgtype() {
return fMsgtype;
}
public void setfMsgtype(String fMsgtype) {
this.fMsgtype = fMsgtype;
}
public String getfDrivercode() {
return fDrivercode;
}
public void setfDrivercode(String fDrivercode) {
this.fDrivercode = fDrivercode;
}
public String getfQrCdrivercode() {
return fQrCdrivercode;
}
public void setfQrCdrivercode(String fQrCdrivercode) {
this.fQrCdrivercode = fQrCdrivercode;
}
public LocalDateTime getfQrFdatetime() {
return fQrFdatetime;
}
public void setfQrFdatetime(LocalDateTime fQrFdatetime) {
this.fQrFdatetime = fQrFdatetime;
}
public String getfQrRandomnum() {
return fQrRandomnum;
}
public void setfQrRandomnum(String fQrRandomnum) {
this.fQrRandomnum = fQrRandomnum;
}
public List<BfsNota1001Detail> getDetails() {
return details;
}
public void setDetails(List<BfsNota1001Detail> details) {
this.details = details;
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("BfsNota1001 [id=");
builder.append(id);
builder.append(", fNotaunikey=");
builder.append(fNotaunikey);
builder.append(", fHead=");
builder.append(fHead);
builder.append(", fMsgtype=");
builder.append(fMsgtype);
builder.append(", fDrivercode=");
builder.append(fDrivercode);
builder.append(", fQrCdrivercode=");
builder.append(fQrCdrivercode);
builder.append(", fQrFdatetime=");
builder.append(fQrFdatetime);
builder.append(", fQrRandomnum=");
builder.append(fQrRandomnum);
builder.append(", details=");
builder.append(details);
builder.append("]");
return builder.toString();
}
}
2.子类(BfsNota1001Detail):
package wjw.test.mybatisplus.slave.vo;
import java.io.Serializable;
import java.time.LocalDateTime;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
public class BfsNota1001Detail implements Serializable {
private static final long serialVersionUID = 1L;
@TableId(type = IdType.AUTO)
/**
* 与业务无关的自增主键
*/
private Long id;
/**
* 标识一条记录的key，由相关的表bfs_nota1001的字段f_notaunikey来赋值
*/
private String fNotaunikey;
/**
* 标识一条记录的key，由业务字段的md5成的32个字节的字符串
*/
private String fDetailunikey;
/**
* 钞口号，长度(字节)
*/
private String fMoneyslogan;
/**
* 把号，长度(字节)
*/
private String fKeynum;
/**
* 银行缩写，长度(字节)
*/
private String fBackcode;
/**
* 银行代码，长度(字节)
*/
private String fDetailbacksx;
/**
* 设备编号，长度(字节)
*/
private String fDrvercode;
/**
* 时间，长度(字节)
*/
private LocalDateTime fBtime;
/**
* 券别，长度(字节)
*/
private String fCoupons;
/**
* 张数，长度(字节)
*/
private Integer fCouponcount;
/**
* 金额，长度(字节)
*/
private Integer fCouponvalue;
/**
* 版本，长度(字节)
*/
private String fRevision;
public BfsNota1001Detail() {
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getfNotaunikey() {
return fNotaunikey;
}
public void setfNotaunikey(String fNotaunikey) {
this.fNotaunikey = fNotaunikey;
}
public String getfDetailunikey() {
return fDetailunikey;
}
public void setfDetailunikey(String fDetailunikey) {
this.fDetailunikey = fDetailunikey;
}
public String getfMoneyslogan() {
return fMoneyslogan;
}
public void setfMoneyslogan(String fMoneyslogan) {
this.fMoneyslogan = fMoneyslogan;
}
public String getfKeynum() {
return fKeynum;
}
public void setfKeynum(String fKeynum) {
this.fKeynum = fKeynum;
}
public String getfBackcode() {
return fBackcode;
}
public void setfBackcode(String fBackcode) {
this.fBackcode = fBackcode;
}
public String getfDetailbacksx() {
return fDetailbacksx;
}
public void setfDetailbacksx(String fDetailbacksx) {
this.fDetailbacksx = fDetailbacksx;
}
public String getfDrvercode() {
return fDrvercode;
}
public void setfDrvercode(String fDrvercode) {
this.fDrvercode = fDrvercode;
}
public LocalDateTime getfBtime() {
return fBtime;
}
public void setfBtime(LocalDateTime fBtime) {
this.fBtime = fBtime;
}
public String getfCoupons() {
return fCoupons;
}
public void setfCoupons(String fCoupons) {
this.fCoupons = fCoupons;
}
public Integer getfCouponcount() {
return fCouponcount;
}
public void setfCouponcount(Integer fCouponcount) {
this.fCouponcount = fCouponcount;
}
public Integer getfCouponvalue() {
return fCouponvalue;
}
public void setfCouponvalue(Integer fCouponvalue) {
this.fCouponvalue = fCouponvalue;
}
public String getfRevision() {
return fRevision;
}
public void setfRevision(String fRevision) {
this.fRevision = fRevision;
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("BfsNota1001Detail [id=");
builder.append(id);
builder.append(", fNotaunikey=");
builder.append(fNotaunikey);
builder.append(", fDetailunikey=");
builder.append(fDetailunikey);
builder.append(", fMoneyslogan=");
builder.append(fMoneyslogan);
builder.append(", fKeynum=");
builder.append(fKeynum);
builder.append(", fBackcode=");
builder.append(fBackcode);
builder.append(", fDetailbacksx=");
builder.append(fDetailbacksx);
builder.append(", fDrvercode=");
builder.append(fDrvercode);
builder.append(", fBtime=");
builder.append(fBtime);
builder.append(", fCoupons=");
builder.append(fCoupons);
builder.append(", fCouponcount=");
builder.append(fCouponcount);
builder.append(", fCouponvalue=");
builder.append(fCouponvalue);
builder.append(", fRevision=");
builder.append(fRevision);
builder.append("]");
return builder.toString();
}
}
Mapper类:
BfsNota1001DetailMapper:
package wjw.test.mybatisplus.slave.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import wjw.test.mybatisplus.slave.vo.BfsNota1001Detail;
@Mapper
public interface BfsNota1001DetailMapper extends BaseMapper<BfsNota1001Detail> {
@Select("select * from bfs_nota1001_detail where f_notaunikey=#{fNotaunikey}")
@Results({@Result(id=true,column="id",property="id"),
@Result(column = "f_notaunikey",property = "fNotaunikey"),
@Result(column = "f_detailunikey",property = "fDetailunikey"),
@Result(column = "f_moneyslogan",property = "fMoneyslogan"),
@Result(column = "f_keynum",property = "fKeynum"),
@Result(column = "f_backcode",property = "fBackcode"),
@Result(column = "f_detailbacksx",property = "fDetailbacksx"),
@Result(column = "f_drvercode",property = "fDrvercode"),
@Result(column = "f_btime",property = "fBtime"),
@Result(column = "f_coupons",property = "fCoupons"),
@Result(column = "f_couponcount",property = "fCouponcount"),
@Result(column = "f_couponvalue",property = "fCouponvalue"),
@Result(column = "f_revision",property = "fRevision")
})
List<BfsNota1001Detail> getListByNotaunikey(@Param("fNotaunikey")String fNotaunikey);
}
BfsNota1001Mapper:
package wjw.test.mybatisplus.slave.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Many;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import wjw.test.mybatisplus.slave.vo.BfsNota1001;
import wjw.test.mybatisplus.slave.vo.BfsNota1001Detail;
@Mapper
public interface BfsNota1001Mapper extends BaseMapper<BfsNota1001> {
//OneToMany一对多查询
@Select("select * from bfs_nota1001 where id=#{id}")
@Results({@Result(column = "id",property = "id",id=true),
@Result(column = "f_notaunikey",property = "fNotaunikey"),
@Result(column = "f_head",property = "fHead"),
@Result(column = "f_msgtype",property = "fMsgtype"),
@Result(column = "f_drivercode",property = "fDrivercode"),
@Result(column = "f_qr_cdrivercode",property = "fQrCdrivercode"),
@Result(column = "f_qr_fdatetime",property = "fQrFdatetime"),
@Result(column = "f_qr_randomnum",property = "fQrRandomnum"),
@Result(column = "f_notaunikey" /* 主查询里的列名,这里的f_notaunikey是要传递给下面查询里需要的参数 */,
property = "details" /* 这里是BfsNota1001Vo类里的details字段 */,many=@Many(
select = "wjw.test.mybatisplus.slave.mapper.BfsNota1001DetailMapper.getListByNotaunikey"
))
})
List<BfsNota1001> getList(@Param("id")Integer id);
}
测试
package wjw.test.mybatisplus;
import java.util.List;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
import org.springframework.test.context.ActiveProfiles;
import wjw.test.mybatisplus.slave.mapper.BfsNota1001DetailMapper;
import wjw.test.mybatisplus.slave.mapper.BfsNota1001Mapper;
import wjw.test.mybatisplus.slave.vo.BfsNota1001;
@SpringBootTest(webEnvironment = WebEnvironment.NONE)
public class MybatisPlusTestSlave {
@Autowired
private BfsNota1001Mapper b1001Mapper;
public MybatisPlusTestSlave() {
//
}
@BeforeEach
public void setup() {
//
}
@AfterEach
public void stop() {
}
@Test
public void get1001() {
List<BfsNota1001> list = b1001Mapper.getList(1);
System.out.println(list);
}
}
输出结果:
w.t.m.slave.mapper.BfsNota1001Mapper.getList - [debug,137] - ==> Preparing: select * from bfs_nota1001 where id=?
w.t.m.slave.mapper.BfsNota1001Mapper.getList - [debug,137] - ==> Parameters: 1(Integer)
w.t.m.slave.mapper.BfsNota1001Mapper.getList - [trace,143] - <== Columns: id, f_notaunikey, f_head, f_msgtype, f_drivercode, f_qr_cdrivercode, f_qr_fdatetime, f_qr_randomnum
w.t.m.slave.mapper.BfsNota1001Mapper.getList - [trace,143] - <== Row: 1, 3c496a9cac5986b5e9dc876f4f0401ff, GDAP20200527, 1001, M02000930, M02000429, 2020-05-27 17:28:39.0, 20022
w.t.m.s.m.B.getListByNotaunikey - [debug,137] - ====> Preparing: select * from bfs_nota1001_detail where f_notaunikey=?
w.t.m.s.m.B.getListByNotaunikey - [debug,137] - ====> Parameters: 3c496a9cac5986b5e9dc876f4f0401ff(String)
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Columns: id, f_notaunikey, f_detailunikey, f_moneyslogan, f_keynum, f_backcode, f_detailbacksx, f_drvercode, f_btime, f_coupons, f_couponcount, f_couponvalue, f_revision
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 1, 3c496a9cac5986b5e9dc876f4f0401ff, e5d73440e633b7783eb3fb957ae60e3, 02, 00019, 51000, 771600110, M02000429, 2020-05-27 17:27:49.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 2, 3c496a9cac5986b5e9dc876f4f0401ff, ad2a34af3038a87f263b8f9ea771e4f1, 02, 00016, 51000, 771600110, M02000429, 2020-05-27 17:27:51.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 3, 3c496a9cac5986b5e9dc876f4f0401ff, 75a42347de99ece9d706dbb7c804ca0d, 02, 00018, 51000, 771600110, M02000429, 2020-05-27 17:27:54.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 4, 3c496a9cac5986b5e9dc876f4f0401ff, 92e78b01edb6e03f3746c284e80ebc73, 02, 00014, 51000, 771600110, M02000429, 2020-05-27 17:27:56.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 5, 3c496a9cac5986b5e9dc876f4f0401ff, b95e2e493947c5f522546b6fa4d3ba3d, 01, 00022, 51000, 771600110, M02000429, 2020-05-27 17:27:59.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 6, 3c496a9cac5986b5e9dc876f4f0401ff, a5efae152a9da726807e5c9a743c1b6d, 01, 00025, 51000, 771600110, M02000429, 2020-05-27 17:28:01.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 7, 3c496a9cac5986b5e9dc876f4f0401ff, 68cb897a34180f92a606aa5a73f20a0b, 02, 00015, 51000, 771600110, M02000429, 2020-05-27 17:28:04.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 8, 3c496a9cac5986b5e9dc876f4f0401ff, 24ffd138d550e59243b1c65504c24d6a, 01, 00017, 51000, 771600110, M02000429, 2020-05-27 17:28:06.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 9, 3c496a9cac5986b5e9dc876f4f0401ff, ff9b18003d7f730a77deabeba6fd453d, 02, 00012, 51000, 771600110, M02000429, 2020-05-27 17:28:09.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [trace,143] - <==== Row: 10, 3c496a9cac5986b5e9dc876f4f0401ff, c9ab32450ec9154b84b3ad98918030e2, 01, 00024, 51000, 771600110, M02000429, 2020-05-27 17:28:12.0, 100, 100, 10000, 2015FIT
w.t.m.s.m.B.getListByNotaunikey - [debug,137] - <==== Total: 10
w.t.m.slave.mapper.BfsNota1001Mapper.getList - [debug,137] - <== Total: 1
[BfsNota1001 [id=1, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fHead=GDAP20200527, fMsgtype=1001, fDrivercode=M02000930, fQrCdrivercode=M02000429, fQrFdatetime=2020-05-27T17:28:39, fQrRandomnum=20022, details=[BfsNota1001Detail [id=1, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=e5d73440e633b7783eb3fb957ae60e3, fMoneyslogan=02, fKeynum=00019, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:27:49, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=2, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=ad2a34af3038a87f263b8f9ea771e4f1, fMoneyslogan=02, fKeynum=00016, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:27:51, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=3, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=75a42347de99ece9d706dbb7c804ca0d, fMoneyslogan=02, fKeynum=00018, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:27:54, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=4, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=92e78b01edb6e03f3746c284e80ebc73, fMoneyslogan=02, fKeynum=00014, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:27:56, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=5, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=b95e2e493947c5f522546b6fa4d3ba3d, fMoneyslogan=01, fKeynum=00022, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:27:59, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=6, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=a5efae152a9da726807e5c9a743c1b6d, fMoneyslogan=01, fKeynum=00025, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:28:01, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=7, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=68cb897a34180f92a606aa5a73f20a0b, fMoneyslogan=02, fKeynum=00015, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:28:04, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=8, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=24ffd138d550e59243b1c65504c24d6a, fMoneyslogan=01, fKeynum=00017, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:28:06, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=9, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=ff9b18003d7f730a77deabeba6fd453d, fMoneyslogan=02, fKeynum=00012, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:28:09, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ], BfsNota1001Detail [id=10, fNotaunikey=3c496a9cac5986b5e9dc876f4f0401ff, fDetailunikey=c9ab32450ec9154b84b3ad98918030e2, fMoneyslogan=01, fKeynum=00024, fBackcode=51000, fDetailbacksx=771600110, fDrvercode=M02000429, fBtime=2020-05-27T17:28:12, fCoupons=100, fCouponcount=100, fCouponvalue=10000, fRevision=2015FIT ]]]]
后记:
MyBatis中常用的一对多查询是 N+1 方式的查询,即先查询主表再查询子表.这就是著名的 [n+1 问题] 。如果记录很多，这种查询效率是非常低效的。
有没有只需要一条SQL查询就能搞定一对多关系的呢? 请看下面的进阶文章Mybatis巧用@Many注解让一条SQL联合查询语句完成一对多查询 !
类似资料：