Q: Can't update model that have one to many association I have this struct in model package
type Item struct {
    LineItemID  uint   `json:"lineItemId" gorm:"primaryKey"`
    ItemCode    string `json:"itemCode"`
    Description string `json:"description"`
    Quantity    int    `json:"quantity"`
    OrderID     int    `json:"-"`
}

type Order struct {
    OrderID      uint      `json:"orderId" gorm:"primaryKey"`
    CustomerName string    `json:"customerName"`
    OrderedAt    time.Time `json:"orderedAt"`
    Items        []Item    `json:"items" gorm:"foreignKey:OrderID"`
}

Then i make handler for update the data:
func UpdateOrderById(c *gin.Context) {
    id := c.Params.ByName("id")

    var order models.Order

    if err := config.DB.Preload("Items").First(&order, id).Error; err != nil {
        c.JSON(http.StatusBadRequest, gin.H{"error": "Record not found!"})
        return
    }

    c.ShouldBindJSON(&order)

    if err := config.DB.Save(&order).Error; err != nil {
        c.JSON(http.StatusBadRequest, gin.H{"error": "Record can't update!"})
        return
    }

    c.JSON(http.StatusOK, order)
}

When i'm trying to use Postman for test my endpoint to update data, order table is successfully updated. But not in item table in database. Anyone can help me please?

A: In this link (https://github.com/go-gorm/gorm/issues/3487) they have the same problem and they specify that in a recent version of GORM it was no longer possible with Save() to update the relations.
But later it is mentioned that they made a change and it would be possible this way:
DB.Session(&gorm.Session{FullSaveAssociations: true}).Save(&order)

https://github.com/go-gorm/gorm/issues/3487#issuecomment-698303344
I haven't been able to test it yet, so I don't know if it works well. Sorry for my English.
Regards
