Gorm 关联 BeforeCreate 回调未按预期工作
我有Customer结构
type Customer struct {
Model
Email string `json:"email,omitempty"`
Addresses []Address
}
func (c *Customer) BeforeCreate() (err error) {
if err := c.GenerateID(); err != nil {
return err
}
return c.Marshal()
}
和Address结构
type Address struct {
Model
CustomerID string
Address1 string
}
func (a *Address) BeforeCreate() error {
// The ID is still generated, but the insert query has no `id` in it
if err := a.GenerateID(); err != nil {
return err
}
return nil
}
Model结构
type Model struct {
ID string `gorm:"primary_key;type:varchar(100)"`
CreatedAt time.Time
UpdatedAt time.Time
DeletedAt *time.Time `sql:"index"`
}
func (model *Model) GenerateID() error {
uv4, err := uuid.NewV4()
if err != nil {
return err
}
model.ID = uv4.String()
return nil
}
一个客户：
customer := &model.Customer{
Email: "a",
Addresses: []model.Address{
{
Address1: "abc street",
},
},
}
if err := gormDb.Create(customer).Error; err != nil {
return nil, err
}
I got an error: Error 1364: Field 'id' doesn't have a default value对于地址对象
但是，如果我删除这些Address关联，一切都会奏效。并Id生成客户。
customer := & model.Customer{
Email: "a",
//Addresses: []model.Address{
//{
//Address1: "abc street",
//},
//},
}
如何保持Address关联并成功插入，并且仍然使用这种 ID 生成机制？
青春有我2回答
-
MYYA
您可以使用scope.SetColumn在BeforeCreate钩子中设置字段的值func (a *Address) BeforeCreate(scope *gorm.Scope) error { scope.SetColumn("ID", uuid.New()) return nil}参考：https ://v1.gorm.io/docs/create.html#Setting-Field-Values-In-Hooks -
幕布斯7119047
您应该使用tx.Statement.SetColumn在 GORM 挂钩中设置字段值，例如BeforeCreate. 以下是示例实现。func (s Product3) BeforeCreate(tx *gorm.DB) (err error) { tx.Statement.SetColumn("Price", s.Price+100) return nil}GORM Github repo 的参考实现链接 https://github.com/go-gorm/gorm/blob/ac722c16f90e0e0dffc600c7f69e791c110d788c/tests/hooks_test.go#L306-L309来自 GORM 文档的参考链接 https://gorm.io/docs/update.html#Change-Updating-Values
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相关分类
Go