@TableId(value = "id",type = IdType.AUTO)//设置主键自增  这里需要注意，设置主键自增的时候不要忘记数据库也要设置主键自增
private Long id;

乐观锁：
1、先查询，获得版本号 version = 1 
-- A 
update user set name = "hekun", version = version + 1 where id = 2 and version = 1 
-- B 线程抢先完成，这个时候 version = 2，会导致 A 修改失败！ 
update user set name = "hekun", version = version + 1 where id = 2 and version = 1

@Bean
public MybatisPlusInterceptor mybatisPlusInterceptor() {
    MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
    interceptor.addInnerInterceptor(new OptimisticLockerInnerInterceptor());
    return interceptor;
}

@Version
private Integer version;

mybatis-plus:
  global-config:
    db-config:
      logic-delete-field: flag # 全局逻辑删除的实体字段名(since 3.3.0,配置后可以忽略不配置步骤2)
      logic-delete-value: 1 # 逻辑已删除值(默认为 1)
      logic-not-delete-value: 0 # 逻辑未删除值(默认为 0)