创建表AutoMigrate，并且插入数据db.Create  

package mainimport ("fmt""gorm.io/driver/mysql""gorm.io/gorm"
)type Student struct {ID     uint   `gorm:"size:3"`Name   string `gorm:"size:3"`Age    int    `gorm:"size:3"`Gender boolEmail  *string `gorm:"size:32"`
}func main() {dsn := "root:7PXjAkY!&nlR@tcp(192.168.11.128:3306)/test?charset=utf8mb4&parseTime=True&loc=Local"db, _ := gorm.Open(mysql.Open(dsn), &gorm.Config{})db.AutoMigrate(&Student{})email := "123@qq.com"//添加记录，实例化结构体s1 := &Student{Name:   "lu",Age:    21,Gender: true,Email:  &email,}err := db.Debug().Create(s1).Errorfmt.Println(err)}[4.019ms] [rows:1] INSERT INTO `students` (`name`,`age`,`gender`,`email`) VALUES ('lu',21,true,'123@qq.com')
<nil>

如果将name和email去注释掉，可以看到string类型的是空字符串，另外一个*string类型的是null。所以email的值可以是Email: nil

	//email := "123@qq.com"//添加记录，实例化结构体s1 := &Student{//Name:   "lu",Age:    21,Gender: true,//Email:  &email,}[3.829ms] [rows:1] INSERT INTO `students` (`name`,`age`,`gender`,`email`) VALUES ('',21,true,NULL)mysql> select * from students;
+----+------+------+--------+------------+
| id | name | age  | gender | email      |
+----+------+------+--------+------------+
|  1 | lu   |   21 |      1 | 123@qq.com |
|  2 |      |   21 |      1 | NULL       |
+----+------+------+--------+------------+

虽然结构体中没有插入ID的值，但是会在结构体当中生成这个值。

	s1 := &Student{//Name:   "lu",Age:    21,Gender: true,Email:  nil,}err := db.Debug().Create(s1).Errorfmt.Printf("%#v \n", s1)[3.833ms] [rows:1] INSERT INTO `students` (`name`,`age`,`gender`,`email`) VALUES ('',21,true,NULL)
&main.Student{ID:0x5, Name:"", Age:21, Gender:true, Email:(*string)(nil)} 

有两个地方需要注意：

1.指针类型是为了更好的存NULL类型，但是传值的时候，也记得传指针

2.Create按收的是一个指针，而不是值

由于我们传递的是一个指针，调用完Create之后，student这个对象上面就有该记录的信息了，如创建的id

批量插入：需要准备切片或者数组，这里create要传入切片的指针

package mainimport ("fmt""gorm.io/driver/mysql""gorm.io/gorm"
)type Student struct {ID     uint   `gorm:"size:3"`Name   string `gorm:"size:3"`Age    int    `gorm:"size:3"`Gender boolEmail  *string `gorm:"size:32"`
}func main() {dsn := "root:7PXjAkY!&nlR@tcp(192.168.11.128:3306)/test?charset=utf8mb4&parseTime=True&loc=Local"db, _ := gorm.Open(mysql.Open(dsn), &gorm.Config{})db.AutoMigrate(&Student{})var studentList []Studentfor i := 0; i < 10; i++ {studentList := append(studentList, Student{Name:   fmt.Sprintf("f%d", i),Age:    21 + i,Gender: true,Email:  nil,})db.Create(&studentList)}slist := []Student{{Name: "cc", Age: 23, Gender: true, Email: nil},{Name: "xx", Age: 24, Gender: false, Email: nil},}db.Create(&slist)
}