mybatis获取自增长id

秒速五厘米 2021-09-28 16:22 405阅读 0赞

## 需求 ##

mybatis在插入数据的同时获取自增长id的值以供接下来的业务使用；

## 代码 ##

### mapper ###

public interface CustomizedConditionMapper {
        //插入数据并返回当前id
        int insertSelective(CustomizedConditionPO customizedConditionPO);
    }

### mapper.xml ###

注意这里要加：useGeneratedKeys="true" keyProperty="id"

<insert id="insertSelective" useGeneratedKeys="true" keyProperty="id" parameterType="com.aikucun.dc.report.dao.model.CustomizedConditionPO" >
        insert into report_customized_condition
        <trim prefix="(" suffix=")" suffixOverrides="," >
          <if test="id != null" >
            id,
          </if>
          <if test="customizedConditionsId != null" >
            customized_conditions_id,
          </if>
          <if test="conditionId != null" >
            condition_id,
          </if>
          <if test="createdTime != null" >
            created_time,
          </if>
          <if test="updatedTime != null" >
            updated_time,
          </if>
          <if test="createdBy != null" >
            created_by,
          </if>
          <if test="updatedBy != null" >
            updated_by,
          </if>
        </trim>
        <trim prefix="values (" suffix=")" suffixOverrides="," >
          <if test="id != null" >
            #{id,jdbcType=INTEGER},
          </if>
          <if test="customizedConditionsId != null" >
            #{customizedConditionsId,jdbcType=INTEGER},
          </if>
          <if test="conditionId != null" >
            #{conditionId,jdbcType=INTEGER},
          </if>
          <if test="createdTime != null" >
            #{createdTime,jdbcType=TIMESTAMP},
          </if>
          <if test="updatedTime != null" >
            #{updatedTime,jdbcType=TIMESTAMP},
          </if>
          <if test="createdBy != null" >
            #{createdBy,jdbcType=VARCHAR},
          </if>
          <if test="updatedBy != null" >
            #{updatedBy,jdbcType=VARCHAR},
          </if>
        </trim>
      </insert>

### 业务代码 ###

注意这边不能直接用

Integer customizedConditionsId=customizedConditionsMapper.insertCustomizedConditions(customizedConditionsPO);

**这个是影响多少行，而应该使用下面的方式获取！！！**

customizedConditionsMapper.insertCustomizedConditions(customizedConditionsPO);
    int customizedConditionsId = customizedConditionsPO.getId();

## 补充说明 ##

该数据表的id务必要设置成自增长！！！