Java + Mybatis Plus 插入数据时ID乱序原因?

Question

mysql自增，id设置成了自增key,有插入失败后id会乱序，比如原来是1，一直失败了5个，到了6。这时候正确插入一条，id返回6。再正确插入一条结果id是5，不知道问题出在哪？

用的是 java + mybatis plus + mysql 8 读写数据，手动无法重现

1.实体类

public class SaledData implements Serializable {

    private static final long serialVersionUID = 1L;
    @TableId(value = "id", type = IdType.AUTO)
    private Long id;
    private LocalDate recordDate; // 设置了唯一约束
    ...
}

2.从远程获取数据并入库

@Scheduled(cron = "0 0 1/1 \* \* ?") 
public void getSaledData() {
    @Resource private ISaledDataService iSaledDataService;
    ...
    SaledData saledData = new SaledData();
    ...
    iSaledDataService.save(saledData); // 有时候数据会重复，会插入失败
}

3.出现的错误结果

        "id": 158,
        "createTime": "2024-05-13T04:00:08",
        "recordDate": "2024-05-12"

        "id": 160,
        "createTime": "2024-05-12T20:00:12",
        "recordDate": "2024-05-11"

Answer 1

很奇怪的问题，跟踪日志发现像是@Scheduled调度线程有的卡住了，本该立即写入库的记录延迟了8个小时后才入库。

@Scheduled(cron = "0 0 1/1 ?", zone = "Asia/Shanghai")
调度加上时区就正常了，没明白是怎么导致的线程延迟