Gorm How to use upsert in bulk data

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What version of Go are you using (go version)?

go version go1.14 linux/amd64

Which database and its version are you using?

Mysql 8.0.20

Please provide a complete runnable program to reproduce your issue. IMPORTANT

Need to runnable with GORM's docker compose config or please provides your config.

package main

import (
    "fmt"
    "log"
    "os"
    "time"

    "gorm.io/driver/mysql"
    "gorm.io/gorm"
    "gorm.io/gorm/clause"
    "gorm.io/gorm/logger"
)

type User struct {
    Id        int
    Name      string
    Address   Address `gorm:"ForeignKey:AddressID;References:id"`
    AddressID int
    Date      *time.Time
}

type Address struct {
    Id       int
    Address1 string
}

var Default = logger.New(log.New(os.Stdout, "\r\n", log.LstdFlags), logger.Config{
    SlowThreshold: 100 * time.Millisecond,
    LogLevel:      logger.Info,
    Colorful:      true,
})

func main() {
    dsn := "root:password@tcp(localhost:3306)/db?charset=utf8&parseTime=True&loc=Local"
    db, _ := gorm.Open(mysql.Open(dsn), &gorm.Config{Logger: Default})

    _ = db.AutoMigrate(&User{}, &Address{})
    now := time.Now()
    users := []User{{Name: "mark", Date: &now, Address: Address{Address1: "address 1"}},
        {Name: "jhon", Date: &now, Address: Address{Address1: "address 2"}}}
    err := db.Create(&users).Error
    fmt.Println(err)

    //Upsert
    users = []User{{Id: 1, Name: "juan"}, {Id: 2, Name: "pedro"}}

    err = db.Clauses(clause.OnConflict{
        Columns:   []clause.Column{{Name: "id"}},
        DoUpdates: clause.Assignments(map[string]interface{}{"name": "????"}), //<-- How update 1->juan, 2->jhon 
    }).Create(&users).Error

    fmt.Println(err)
}

I am trying to update the record with ID 1 with the name "juan" and the record with ID 2 with the name pedro, how can I do it?


**Comment From: jinzhu**

> I am trying to update the record with ID 1 with the name "juan" and the record with ID 2 with the name pedro, how can I do it?

We can't support update a column to different values when batch insert due to SQL limitation ;(

**Comment From: jinzhu**

But you can do a batch update like this:

https://www.tutorialspoint.com/mysql-mass-update-with-case-when-then-else

It would be possible to make GORM support this if it is what you want...

**Comment From: efrengarcial**

> We can't support update a column to different values when batch insert due to SQL limitation ;(

Excuse my ignorance, it is possible to generate the SQL this way:

Mysql case
INSERT INTO `users` (`name`,`address_id`,`date`,`id`) VALUES ("juan",0,NULL,1),("pedro",0,NULL,2) ON DUPLICATE KEY UPDATE `name`=**values(name)**

Postgres and Sqlite cases
INSERT INTO `users` (`name`,`address_id`,`date`,`id`) VALUES ("juan",0,NULL,1),("pedro",0,NULL,2) ON CONFLICT (id) DO UPDATE SET `name`=**excluded.name**


**Comment From: jinzhu**

Good to know, let me think how to make the API works with that.

**Comment From: jinzhu**

```go
db.Clauses(clause.OnConflict{
  Columns:   []clause.Column{{Name: "id"}},
  DoUpdates: clause.AssignmentColumns([]{"name"}),
}).Create(&users).Error

Comment From: efrengarcial

works fine thanks a lot.