golang gin gorm插入并设置primary_key，但primary_key为空

import (
    "github.com/gin-gonic/gin"
    "gorm.io/gorm"
)

type User struct {
    ID   uint   `gorm:"primaryKey"`
    Name string `gorm:"not null"`
    Age  int
}

func createUser(c *gin.Context) {
    var user User
    if err := c.ShouldBindJSON(&user); err != nil {
        c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
        return
    }

    // 手动设置主键为空
    user.ID = 0

    // 插入数据
    if err := db.Create(&user).Error; err != nil {
        c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
        return
    }

    c.JSON(http.StatusOK, gin.H{"message": "User created successfully", "data": user})
}

router := gin.Default()
router.POST("/users", createUser)