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;