c# - MySqlException : Field 'id' doesn't have a default value - Entity Framework Core 2. 1

Question

我是 ASP.NET Core MVC 的新手。我在使用 Entity Framework 核心向 MySQL 插入数据时遇到错误。调试时我得到了由上下文分配的 minus(-2147482645) 中的 id。为什么 id 是由 EF 分配的？如何解决这个错误？ MySQL id 列中的表是 NOTNULL，PK 和 Auto Increment 设置为默认值。

这是我的 DBContextFile

    {
        public AppDbContext(DbContextOptions<AppDbContext> options)
            : base(options)
        { }

        public DbSet<PCBDesign> pCBDesigns { get; set; }



        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);
        }
    }

这是我的类(class)

    {

        [Key]
        public int id { get; set; }
        public string userId { get; set; }
        public string desginNo { get; set; }
        public DateTime Crdate { get; set; }
        public string name { get; set; }
        public string contact { get; set; }
        public string notes { get; set; }
    }

调用后 context.SaveChanges();获取错误:

Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while updating the entries. See the inner exception for details. ---> MySql.Data.MySqlClient.MySqlException: Field 'id' doesn't have a default value ---> MySql.Data.MySqlClient.MySqlException: Field 'id' doesn't have a default value

建表查询:

DROP TABLE IF EXISTS `pcbdesigns`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!50503 SET character_set_client = utf8mb4 */;
CREATE TABLE `pcbdesigns` (
  `id` int NOT NULL AUTO_INCREMENT,
  `userId` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci,
  `desginNo` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci,
  `Crdate` datetime NOT NULL,
  `name` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci,
  `contact` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci,
  `notes` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;
/*!40101 SET character_set_client = @saved_cs_client */;

--
-- Dumping data for table `pcbdesigns`
--

LOCK TABLES `pcbdesigns` WRITE;
/*!40000 ALTER TABLE `pcbdesigns` DISABLE KEYS */;
INSERT INTO `pcbdesigns` VALUES ();
/*!40000 ALTER TABLE `pcbdesigns` ENABLE KEYS */;
UNLOCK TABLES;`

Answer 1

问题解决了!第 1 步: 为每个表复制表创建脚本第 2 步: 从同一脚本创建的删除表。第 3 步:在表中添加一个虚拟行。

附加信息:我确实从代码优先方法进行了迁移，我认为迁移时 Entity Framework Core 存在一些问题。从现在开始，我不会进行迁移，这会给我带来更多错误。

谢谢。