Delete

Delete a Record

When deleting a record, the deleted value needs to have primary key or it will trigger a Batch Delete, for example:

// Email's ID is `10`
db.Delete(&email)
// DELETE from emails where id = 10;

// Delete with additional conditions
db.Where("name = ?", "jinzhu").Delete(&email)
// DELETE from emails where id = 10 AND name = "jinzhu";

Delete with primary key

GORM allows to delete objects using primary key(s) with inline condition, it works with numbers, check out Query Inline Conditions for details

db.Delete(&User{}, 10)
// DELETE FROM users WHERE id = 10;

db.Delete(&User{}, "10")
// DELETE FROM users WHERE id = 10;

db.Delete(&users, []int{1,2,3})
// DELETE FROM users WHERE id IN (1,2,3);

Delete Hooks

GORM allows hooks BeforeDelete, AfterDelete, those methods will be called when deleting a record, refer Hooks for details

func (u *User) BeforeDelete(tx *gorm.DB) (err error) {
  if u.Role == "admin" {
    return errors.New("admin user not allowed to delete")
  }
  return
}

Batch Delete

The specified value has no primary value, GORM will perform a batch delete, it will delete all matched records

db.Where("email LIKE ?", "%jinzhu%").Delete(&Email{})
// DELETE from emails where email LIKE "%jinzhu%";

db.Delete(&Email{}, "email LIKE ?", "%jinzhu%")
// DELETE from emails where email LIKE "%jinzhu%";

Block Global Delete

If you perform a batch delete without any conditions, GORM WON’T run it, and will return ErrMissingWhereClause error

You have to use some conditions or use raw SQL or enable AllowGlobalUpdate mode, for example:

db.Delete(&User{}).Error // gorm.ErrMissingWhereClause

db.Where("1 = 1").Delete(&User{})
// DELETE FROM `users` WHERE 1=1

db.Exec("DELETE FROM users")
// DELETE FROM users

db.Session(&gorm.Session{AllowGlobalUpdate: true}).Delete(&User{})
// DELETE FROM users

Returning Data From Deleted Rows

Return deleted data, only works for database support Returning, for example:

// return all columns
var users []User
DB.Clauses(clause.Returning{}).Where("role = ?", "admin").Delete(&users)
// DELETE FROM `users` WHERE role = "admin" RETURNING *
// users => []User{{ID: 1, Name: "jinzhu", Role: "admin", Salary: 100}, {ID: 2, Name: "jinzhu.2", Role: "admin", Salary: 1000}}

// return specified columns
DB.Clauses(clause.Returning{Columns: []clause.Column{{Name: "name"}, {Name: "salary"}}}).Where("role = ?", "admin").Delete(&users)
// DELETE FROM `users` WHERE role = "admin" RETURNING `name`, `salary`
// users => []User{{ID: 0, Name: "jinzhu", Role: "", Salary: 100}, {ID: 0, Name: "jinzhu.2", Role: "", Salary: 1000}}

Soft Delete

If your model includes a gorm.DeletedAt field (which is included in gorm.Model), it will get soft delete ability automatically!

When calling Delete, the record WON’T be removed from the database, but GORM will set the DeletedAt‘s value to the current time, and the data is not findable with normal Query methods anymore.

// user's ID is `111`
db.Delete(&user)
// UPDATE users SET deleted_at="2013-10-29 10:23" WHERE id = 111;

// Batch Delete
db.Where("age = ?", 20).Delete(&User{})
// UPDATE users SET deleted_at="2013-10-29 10:23" WHERE age = 20;

// Soft deleted records will be ignored when querying
db.Where("age = 20").Find(&user)
// SELECT * FROM users WHERE age = 20 AND deleted_at IS NULL;

If you don’t want to include gorm.Model, you can enable the soft delete feature like:

type User struct {
  ID      int
  Deleted gorm.DeletedAt
  Name    string
}

Find soft deleted records

You can find soft deleted records with Unscoped

db.Unscoped().Where("age = 20").Find(&users)
// SELECT * FROM users WHERE age = 20;

Delete permanently

You can delete matched records permanently with Unscoped

db.Unscoped().Delete(&order)
// DELETE FROM orders WHERE id=10;

Delete Flag

Use unix second as delete flag

import "gorm.io/plugin/soft_delete"

type User struct {
  ID        uint
  Name      string
  DeletedAt soft_delete.DeletedAt
}

// Query
SELECT * FROM users WHERE deleted_at = 0;

// Delete
UPDATE users SET deleted_at = /* current unix second */ WHERE ID = 1;

INFO when using unique field with soft delete, you should create a composite index with the unix second based DeletedAt field, e.g:

import "gorm.io/plugin/soft_delete"

type User struct {
  ID        uint
  Name      string                `gorm:"uniqueIndex:udx_name"`
  DeletedAt soft_delete.DeletedAt `gorm:"uniqueIndex:udx_name"`
}

Use 1 / 0 as delete flag

import "gorm.io/plugin/soft_delete"

type User struct {
  ID    uint
  Name  string
  IsDel soft_delete.DeletedAt `gorm:"softDelete:flag"`
}

// Query
SELECT * FROM users WHERE is_del = 0;

// Delete
UPDATE users SET is_del = 1 WHERE ID = 1;