Redis数据同步到Mysql

数据同步到Mysql"/>

Redis数据同步到Mysql

概述

秒杀系统中总需要在启动时将数据放到redis中，即缓存预热，在秒杀开始时则需要通过redis进行库存的扣减，为保证redis和mysql数据一致性，通过可通过定时任务将redis中的数据同步回mysql中

demo

我们知道Redis数据的key通常以类名:midKey:商品id进行设计，为此我们根据key取出数据来，更新到数据库即可

@Component
public class RedisToMySqlScheduled implements ApplicationRunner {@Autowiredprivate GoodsService goodsService;@Autowiredprivate RedisUtil redisUtil;//map用来做数据的缓存private Map<Long,Boolean> map = new ConcurrentHashMap<>();@Scheduled(cron = "15 05 11 * * ? ")public void redisDataToMySql(){if (!map.isEmpty()){map.entrySet().forEach(entry->{Integer count = redisUtil.get(GoodsKey.getSecondKillGoodsStock, ":" + entry.getKey(), Integer.class);goodsService.redisToMysql(count,entry.getKey());});}}@Overridepublic void run(ApplicationArguments args) throws Exception {//取出全部数据List<GoodsVo> goodsVos = goodsService.listGoodsVo();goodsVos.forEach(e->{map.put(e.getId(),false);});}
}

service

public int redisToMysql(Integer count,Long goodId){return goodsDao.redisDataToMysql(count,goodId);}

mapper

@Update("update second_goods set stock_count = #{stockCount} where goods_id = #{goodsId}")int redisDataToMysql(@Param("stockCount")Integer stockCount,@Param("goodsId")Long goodsId);

demo地址