目前有業務併發更新某業務表,好比用戶帳戶表,可考慮利用數據庫樂觀鎖的辦法解決。數據庫
一、表設計mybatis
須要在表中新增version字段,可定義爲bigint類型,初始值可設置爲0併發
二、更新語句mybatis的實現app
<update id="updateConsumeStarWithLook"> update sys_user_consume_star set current_consume_star_amount = #{currentConsumeStarAmount}, update_time = #{updateTime, jdbcType=TIMESTAMP}, version = version + 1 where id = #{id} and version = #{version} </update>
三、業務邏輯層,實現思路:可定義一個更新方法,先查詢出當前記錄,根據業務進行調用樂觀鎖實現的updateConsumeStarWithLook,若是更新成功,即該返回值爲1時,表示更新成功,當返回值爲0時,表示未成功更新,可再次遞歸調用該更新方法。測試
private void updateUserConsumeStarWithLook(String userId,Long starAmount) { Wrapper<SysUserConsumeStar> wrapper = new QueryWrapper<SysUserConsumeStar>() .eq("user_id", userId); SysUserConsumeStar sysUserConsumeStar = sysUserConsumeStarService.getOne(wrapper); Long oldStartAmount = sysUserConsumeStar.getCurrentConsumeStarAmount(); Long newStartAmount = oldStartAmount + starAmount; sysUserConsumeStar.setCurrentConsumeStarAmount(newStartAmount).setUpdateTime(LocalDateTime.now()); Integer result = sysUserConsumeStarService.updateConsumeStarWithLook(sysUserConsumeStar); //若是更新失敗則繼續嘗試直到成功爲止
if(result == 0) { updateUserConsumeStarWithLook(userId,flowType,starAmount); } }
四、在具體調用上述方法的方法上若是須要加上事務,則須要將事務的隔離級別定義爲讀已提交,否則在查詢的時候會出現髒讀,更新沒法成功,致使死循環spa
@Transactional(rollbackFor = Exception.class,isolation=Isolation.READ_COMMITTED,propagation=Propagation.REQUIRED)
五、測試,可以使用JMater,相關教程可參考:https://blog.csdn.net/u010481688/article/details/81032259.net