解决Spring或SpringBoot开启事务以后无法返回自增主键的问题

spring或springboot开启事务以后无法返回自增主键

场景：保存订单和订单详情，订单详情需要订单id，数据库中的订单表是自增主键，开启事务后，导致订单主键无法返回

1、开启事务前（以下代码只是样例，实际可能无法运行）

ordermapper.xml配置

<?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="cn.test.mapper.ordermapper" >
  <!-- 创建商品订单 -->
  <insert id="creategoodsorder" parametertype="cn.test.pojo.dto.goodsorderdto" usegeneratedkeys="true" keyproperty="orderid">
    insert into goods_order (
        order_no, shop_id, account_id, total_original_price, total_discount_price, total_price, order_status, order_source, goods_statement_no, create_time
    ) values (
        #{orderno}, #{shopid}, #{accountid}, #{totaloriginalprice}, #{totaldiscountprice}, #{totalprice}, #{orderstatus}, #{ordersource}, #{goodsstatementno}, #{createtime}
    )
  </insert>
  <!-- 创建商品订单详情 -->
  <insert id="creategoodsorderdetail" parametertype="cn.test.pojo.dto.goodsorderdetaildto" >
    insert into goods_order_detail (
        order_id, goods_sku_id, goods_num, original_price, discount_price, price, create_time
    ) values (
        #{orderid}, #{skuid}, #{goodsnum}, #{originalprice}, #{discountprice}, #{price}, #{createtime}
    )
  </insert>
</mapper>

ordermapper.java

package cn.test.mapper;
import cn.test.pojo.dto.goodsorderdto;
import cn.test.pojo.dto.goodsorderdetaildto;
import org.apache.ibatis.annotations.mapper;
@mapper
public interface ordermapper {
    /**
     * 创建商品订单
     *
     * @param goodsorderdto
     * @return
     */
    void creategoodsorder(goodsorderdto goodsorderdto);
    /**
     * 创建商品订单详情
     *
     * @param goodsorderdetaildto
     */
    void creategoodsorderdetail(goodsorderdetaildto goodsorderdetaildto);
}

orderservice.java

package cn.test.service;
import cn.test.pojo.vo.creategoodsordervo;
import cn.tesst.pojo.bo.createorderbo;
public interface orderservice {
    /**
     * 创建商品订单
    * @param createorderbo
    * @return
    */
   creategoodsordervo creategoodsorder(createorderbo createorderbo);  
}

orderserviceimpl.java

package cn.test.service.impl;
import cn.test.pojo.vo.creategoodsordervo;
import cn.test.pojo.bo.createorderbo;
import cn.test.utils.ordersutil;
import cn.test.constant.enums.orderstatusenums;
@service
public class orderserviceimpl implements orderservice {
   /**
    * 创建商品订单
    * @param createorderbo
    * @return
    */
   @override
   public creategoodsordervo creategoodsorder(createorderbo createorderbo) {
       // 1 生成订单
       goodsorderdto goodsorderdto = new goodsorderdto();
       // 1.1 生成订单号
       string orderno = orderprefix + ordersutil.createorderno();
       // 1.2 封装订单实体类
       goodsorderdto.setorderno(orderno);
       goodsorderdto.setshopid(shopid);
       goodsorderdto.setaccountid(createorderbo.getaccountid());
       // 数据库按分处理
       goodsorderdto.settotalprice(totalprice);
       goodsorderdto.settotaloriginalprice(totaloriginalprice);
       goodsorderdto.settotaldiscountprice(totaloriginalprice - totalprice);
       goodsorderdto.setordersource(createorderbyshopbo.getordersource());
       goodsorderdto.setorderstatus(orderstatusenums.create_order_success.getcode());
       goodsorderdto.setgoodsstatementno(statementno);
       goodsorderdto.setcreatetime(datestring);
       // 1.3 创建订单
       ordermapper.creategoodsorder(goodsorderdto);
       
       // 2 封装订单详情
       goodsorderdetaildto goodsorderdetaildto = new goodsorderdetaildto();
       goodsorderdetaildto.setorderid(goodsorderdto.getorderid());　　//不开启事务可以获取到订单自增主键
       goodsorderdetaildto.setskuid(skuid);
       goodsorderdetaildto.setgoodsnum(buycounts);
       goodsorderdetaildto.setoriginalprice(originalprice);
       goodsorderdetaildto.setdiscountprice(originalprice - price);
       goodsorderdetaildto.setprice(price);
       goodsorderdetaildto.setcreatetime(datestring);
       // todo  查询库存、减库存
       // 2.1创建订单详情
       ordermapper.creategoodsorderdetail(goodsorderdetaildto);
       
       // 3 返回订单实体类
       creategoodsordervo creategoodsordervo = new creategoodsordervo();
       creategoodsordervo.setorderno(orderno);
       creategoodsordervo.settotalprice(totalprice);
       creategoodsordervo.setcreatetime(datestring);
       return creategoodsordervo;
   }
}

2、开启事务后（只修改了ordermapper.xml和orderserviceimpl.java）

ordermapper.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="cn.test.mapper.ordermapper" > 
 
   <!-- 创建商品订单 -->
   <insert id="creategoodsorder" parametertype="cn.test.pojo.dto.goodsorderdto" >
     <selectkey resulttype="java.lang.integer" keyproperty="orderid">
      select last_insert_id()
    </selectkey>
    insert into goods_order (
        id,order_no, shop_id, account_id, total_original_price, total_discount_price, total_price, order_status, order_source, goods_statement_no, create_time
    ) values (
        #{orderid},#{orderno}, #{shopid}, #{accountid}, #{totaloriginalprice}, #{totaldiscountprice}, #{totalprice}, #{orderstatus}, #{ordersource}, #{goodsstatementno}, #{createtime}
    )
  </insert>
  
  <!-- 创建商品订单详情 -->
  <insert id="creategoodsorderdetail" parametertype="cn.test.pojo.dto.goodsorderdetaildto" >
    insert into goods_order_detail (
        order_id, goods_sku_id, goods_num, original_price, discount_price, price, create_time
    ) values (
        #{orderid}, #{skuid}, #{goodsnum}, #{originalprice}, #{discountprice}, #{price}, #{createtime}
    )
  </insert>
</mapper>

orderserviceimpl.java

package cn.test.service.impl;
import cn.test.pojo.vo.creategoodsordervo;
import cn.test.pojo.bo.createorderbo;
import cn.test.utils.ordersutil;
import cn.test.constant.enums.orderstatusenums;
@service
public class orderserviceimpl implements orderservice {
    /**
     * 创建商品订单
     * @param createorderbo
     * @return
     */
    @transactional(propagation = propagation.required, rollbackfor = exception.class)
    @override
    public creategoodsordervo creategoodsorder(createorderbo createorderbo) {
        // 1 生成订单
        goodsorderdto goodsorderdto = new goodsorderdto();
        // 1.1 生成订单号
        string orderno = orderprefix + ordersutil.createorderno();
        // 1.2 封装订单实体类
        goodsorderdto.setorderno(orderno);
        goodsorderdto.setshopid(shopid);
        goodsorderdto.setaccountid(createorderbo.getaccountid());
        // 数据库按分处理
        goodsorderdto.settotalprice(totalprice);
        goodsorderdto.settotaloriginalprice(totaloriginalprice);
        goodsorderdto.settotaldiscountprice(totaloriginalprice - totalprice);
        goodsorderdto.setordersource(createorderbyshopbo.getordersource());
        goodsorderdto.setorderstatus(orderstatusenums.create_order_success.getcode());
        goodsorderdto.setgoodsstatementno(statementno);
        goodsorderdto.setcreatetime(datestring);
        // 1.3 创建订单
        ordermapper.creategoodsorder(goodsorderdto);
        
        // 2 封装订单详情
        goodsorderdetaildto goodsorderdetaildto = new goodsorderdetaildto();
        goodsorderdetaildto.setorderid(goodsorderdto.getorderid());
        goodsorderdetaildto.setskuid(skuid);
        goodsorderdetaildto.setgoodsnum(buycounts);
        goodsorderdetaildto.setoriginalprice(originalprice);
        goodsorderdetaildto.setdiscountprice(originalprice - price);
        goodsorderdetaildto.setprice(price);
        goodsorderdetaildto.setcreatetime(datestring);
        // todo  查询库存、减库存
        // 2.1创建订单详情
        ordermapper.creategoodsorderdetail(goodsorderdetaildto);
        
        // 3 返回订单实体类
        creategoodsordervo creategoodsordervo = new creategoodsordervo();
        creategoodsordervo.setorderno(orderno);
        creategoodsordervo.settotalprice(totalprice);
        creategoodsordervo.setcreatetime(datestring);
        return creategoodsordervo;
    }    
}

orderserviceimpl.java中添加事务后，需要在ordermapper.xml使用 select last_insert_id()。

springboot整合mybatis获得插入数据后的主键，返回的一直是1(已解决)

mybatis如何获得自增主键id，此处我不再叙述，网上有很多，这里就记录一下我遇到的问题。

先看一下我获得主键的部分sql代码：

<insert id="save" parametertype="com.test.domain.carddo" 
  
  keyproperty="cardid" usegeneratedkeys="true" >
         
         insert into test
         <trim prefix="(" suffix=")" suffixoverrides=",">
         ......

我采用keyproperty的方式获取主键，我的实体类上也有对应的属性cardid，而我数据库的主键card_id也是自增的，但是获得的值一直是1？！！！

em…难道是我启动项目的姿势不对？要不我换个妖娆的姿势启动看看？莫非代码也看脸？

几经周转才发现原来是因为我service层获得主键id的方式不对，下面是我错误的写法：

@override
@transactional
public int save(carddo carddo,long personid) {
        persondo persondo=new persondo();
        
        //看见了吗，就是这句代码，这是错误的获取id的方式！错误的！错误的！
        long cardid=carddao.save(carddo);
        
        persondo.setcardid(cardid);
        persondo.setpersonid(personid);
        return persondao.update(persondo);
}

关键就在上面那句有注释的代码，save方法返回的是影响行数而不是主键id，实际上，在我们向数据库插入数据，获得此条数据的主键后是存储在我们的实体类中的，至于存储在实体类的哪一个属性中，那就要看keyproperty设置的值是什么了。

所以获得主键直接用这个实体类对应的属性的get方法获得就好了。

如下贴出我正确的代码：

@override
@transactional
public int save(carddo carddo,long personid) {
        persondo persondo=new persondo();
        //插入数据
        carddao.save(carddo);
        
        //获取主键
        long cardid=carddo.getcardid()
        
        persondo .setcardid(cardid);
        persondo .setpersonid(personid);
        return persondao.update(persondo);
}

以上为个人经验，希望能给大家一个参考，也希望大家多多支持。