Gorm Bulk Upsert is a library to implement bulk INSERT ... ON DUPLICATE KEY UPDATE using gorm. Execute bulk upsert just by passing a slice of struct, as if you were using a gorm regularly.

Inspired by gorm-bulk-insert

When saving a large number of records in database, inserting at once - instead of inserting one by one - leads to significant performance improvement. This is widely known as bulk insert.

Gorm is one of the most popular ORM and contains very developer-friendly features, but bulk insert is not provided.

This library is aimed to solve the bulk insert problem.

$ go get github.com/atcdot/gorm-bulk-upsert

This library depends on gorm, following command is also necessary unless you've installed gorm.

$ go get github.com/jinzhu/gorm

gormbulk.BulkUpsert(db, sliceValue, 3000)

Third argument specifies the maximum number of records to bulk upsert at once. This is because inserting a large number of records and embedding variable at once will exceed the limit of prepared statement.

Depending on the number of variables included, 2000 to 3000 is recommended.

gormbulk.BulkUpsert(db, sliceValue, 3000, "Name", "Email")

Basically, upserting struct values are automatically chosen. However if you want to exclude some columns explicitly, you can specify as argument.

In the above pattern Name and Email fields are excluded.

• Just pass a slice of struct as using gorm normally, records will be created.
  • NOTE: passing value must be a slice of struct. Map or other values are not compatible.
• CreatedAt and UpdatedAt are automatically set to the current time.
• Fields of relation such as belongsTo and hasMany are automatically excluded, but foreignKey is subject to Insert.

package main

import (
	"fmt"
	"github.com/jinzhu/gorm"
	"github.com/atcdot/gorm-bulk-upsert"
	"log"
	"time"
	_ "github.com/jinzhu/gorm/dialects/mysql"
)

type fakeTable struct {
	ID        int
	Name      string
	Email     string
	CreatedAt time.Time
	UpdatedAt time.Time
}

func main() {
	db, err := gorm.Open("mysql", "mydb")
	if err != nil {
		log.Fatal(err)
	}

	var upsertRecords []interface{}
	for i := 0; i < 10; i++ {
		upsertRecords = append(upsertRecords,
			fakeTable{
				Name:  fmt.Sprintf("name%d", i),
				Email: fmt.Sprintf("test%[email protected]", i),
				// you don't need to set CreatedAt, UpdatedAt
			},
		)
	}

	err = gormbulkups.BulkUpsert(db, upsertRecords, 3000)
	if err != nil {
		// do something
	}

	// columns you want to exclude from Upsert, specify as an argument
	err = gormbulkups.BulkUpsert(db, upsertRecords, 3000, "Email")
        if err != nil {
            // do something
        }
}

This project is under Apache 2.0 License. See the LICENSE file for the full license text.