Answer a question

gorm tell in the documentation that "Base model definition gorm.Model, including fields ID, CreatedAt, UpdatedAt, DeletedAt, you could embed it in your model, or only write those fields you want":

// Base Model's definition
type Model struct {
  ID        uint `gorm:"primary_key"`
  CreatedAt time.Time
  UpdatedAt time.Time
  DeletedAt *time.Time
}

// Add fields `ID`, `CreatedAt`, `UpdatedAt`, `DeletedAt`
type User struct {
  gorm.Model
  Name string
}

// Only need field `ID`, `CreatedAt`
type User struct {
  ID        uint
  CreatedAt time.Time
  Name      string
}
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Following the documentation, I expect to have only one definition of User, so I create an object like that:

type User struct {
  gorm.Model
  ID        uint
  CreatedAt time.Time
  Name      string
}
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But if I do a DB.CreateTable(&User{}), I get the following errors from postgres:

(pq: column "id" specified more than once)
(pq: column "created_at" specified more than once)
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So I have to have two different objects :

type CreateUser struct {
  gorm.Model
  Name string
}

type RetrieveUser struct {
  gorm.Model
  ID        uint
  CreatedAt time.Time
  Name      string
}
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So I can do a DB.CreateTable(&CreateUser{})

It is very ugly and I must be missing something, any idea?

Answers

Ok, just read the code behind gorm.Model and I got my answer.

type Model struct {
    ID        uint `gorm:"primary_key"`
    CreatedAt time.Time
    UpdatedAt time.Time
    DeletedAt *time.Time `sql:"index"`
}
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It means I just learned how inheritance works in go !