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CRUD Interface

Update

qianmoQqianmoQ· 更新于 2026-09-13· 阅读 26 分钟· 0 次阅读
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Save All Fields

Traditional API

Save will save all fields when performing the Updating SQL

db.First(&user)

user.Name = "jinzhu 2"
user.Age = 100
db.Save(&user)

Save is an upsert function:

  • If the value contains no primary key, it performs Create
  • If the value has a primary key, it first executes Update (all fields, by Select(*)).
  • If rows affected = 0 after Update, it automatically falls back to Create.

💡 Note: Save guarantees either an update or insert will occur.
To prevent unintended creation when no rows match, use Select(*).Updates() .

db.Save(&User{Name: "jinzhu", Age: 100})


db.Save(&User{ID: 1, Name: "jinzhu", Age: 100})

NOTE Don’t use Save with Model, it’s an Undefined Behavior.

NOTE The Save method is intentionally removed from the Generics API to prevent ambiguity and concurrency issues. Please use Create or Updates methods instead.

Update single column

When updating a single column with Update, it needs to have any conditions or it will raise error ErrMissingWhereClause, checkout Block Global Updates for details.

Generics API

ctx := context.Background()


err := gorm.G[User](db).Where("active = ?", true).Update(ctx, "name", "hello")



err := gorm.G[User](db).Where("id = ?", 111).Update(ctx, "name", "hello")



err := gorm.G[User](db).Where("id = ? AND active = ?", 111, true).Update(ctx, "name", "hello")

Traditional API

When using the Model method and its value has a primary value, the primary key will be used to build the condition, for example:


db.Model(&User{}).Where("active = ?", true).Update("name", "hello")



db.Model(&user).Update("name", "hello")



db.Model(&user).Where("active = ?", true).Update("name", "hello")

Updates multiple columns

Updates supports updating with struct or map[string]interface{}, when updating with struct it will only update non-zero fields by default

Generics API

ctx := context.Background()


rows, err := gorm.G[User](db).Where("id = ?", 111).Updates(ctx, User{Name: "hello", Age: 18, Active: false})



rows, err := gorm.G[map[string]interface{}](db).Table("users").Where("id = ?", 111).Updates(ctx, map[string]interface{}{"name": "hello", "age": 18, "active": false})

Traditional API


db.Model(&user).Updates(User{Name: "hello", Age: 18, Active: false})



db.Model(&user).Updates(map[string]interface{}{"name": "hello", "age": 18, "active": false})

NOTE When updating with struct, GORM will only update non-zero fields. You might want to use map to update attributes or use Select to specify fields to update

Update Selected Fields

If you want to update selected fields or ignore some fields when updating, you can use Select, Omit

Generics API

ctx := context.Background()


rows, err := gorm.G[User](db).Where("id = ?", 111).Select("name").Updates(ctx, map[string]interface{}{"name": "hello", "age": 18, "active": false})


rows, err := gorm.G[User](db).Where("id = ?", 111).Omit("name").Updates(ctx, map[string]interface{}{"name": "hello", "age": 18, "active": false})



rows, err := gorm.G[User](db).Where("id = ?", 111).Select("Name", "Age").Updates(ctx, User{Name: "new_name", Age: 0})



rows, err := gorm.G[User](db).Where("id = ?", 111).Select("*").Updates(ctx, User{Name: "jinzhu", Role: "admin", Age: 0})


rows, err := gorm.G[User](db).Where("id = ?", 111).Select("*").Omit("Role").Updates(ctx, User{Name: "jinzhu", Role: "admin", Age: 0})

Traditional API



db.Model(&user).Select("name").Updates(map[string]interface{}{"name": "hello", "age": 18, "active": false})


db.Model(&user).Omit("name").Updates(map[string]interface{}{"name": "hello", "age": 18, "active": false})



db.Model(&user).Select("Name", "Age").Updates(User{Name: "new_name", Age: 0})



db.Model(&user).Select("*").Updates(User{Name: "jinzhu", Role: "admin", Age: 0})


db.Model(&user).Select("*").Omit("Role").Updates(User{Name: "jinzhu", Role: "admin", Age: 0})

Update Hooks

GORM allows the hooks BeforeSave, BeforeUpdate, AfterSave, AfterUpdate. Those methods will be called when updating a record, refer Hooks for details

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

Batch Updates

If we haven’t specified a record having a primary key value with Model, GORM will perform a batch update


db.Model(User{}).Where("role = ?", "admin").Updates(User{Name: "hello", Age: 18})



db.Table("users").Where("id IN ?", []int{10, 11}).Updates(map[string]interface{}{"name": "hello", "age": 18})

Block Global Updates

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

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

db.Model(&User{}).Update("name", "jinzhu").Error 

db.Model(&User{}).Where("1 = 1").Update("name", "jinzhu")


db.Exec("UPDATE users SET name = ?", "jinzhu")


db.Session(&gorm.Session{AllowGlobalUpdate: true}).Model(&User{}).Update("name", "jinzhu")

Updated Records Count

Get the number of rows affected by a update


result := db.Model(User{}).Where("role = ?", "admin").Updates(User{Name: "hello", Age: 18})


result.RowsAffected 
result.Error

Advanced

Update with SQL Expression

GORM allows updating a column with a SQL expression, e.g:


db.Model(&product).Update("price", gorm.Expr("price * ? + ?", 2, 100))


db.Model(&product).Updates(map[string]interface{}{"price": gorm.Expr("price * ? + ?", 2, 100)})


db.Model(&product).UpdateColumn("quantity", gorm.Expr("quantity - ?", 1))


db.Model(&product).Where("quantity > 1").UpdateColumn("quantity", gorm.Expr("quantity - ?", 1))

And GORM also allows updating with SQL Expression/Context Valuer with Customized Data Types, e.g:


type Location struct {
  X, Y int
}

func (loc Location) GormValue(ctx context.Context, db *gorm.DB) clause.Expr {
  return clause.Expr{
    SQL:  "ST_PointFromText(?)",
    Vars: []interface{}{fmt.Sprintf("POINT(%d %d)", loc.X, loc.Y)},
  }
}

db.Model(&User{ID: 1}).Updates(User{
  Name:  "jinzhu",
  Location: Location{X: 100, Y: 100},
})

Update from SubQuery

Update a table by using SubQuery

db.Model(&user).Update("company_name", db.Model(&Company{}).Select("name").Where("companies.id = users.company_id"))


db.Table("users as u").Where("name = ?", "jinzhu").Update("company_name", db.Table("companies as c").Select("name").Where("c.id = u.company_id"))

db.Table("users as u").Where("name = ?", "jinzhu").Updates(map[string]interface{}{"company_name": db.Table("companies as c").Select("name").Where("c.id = u.company_id")})

Without Hooks/Time Tracking

If you want to skip Hooks methods and don’t track the update time when updating, you can use UpdateColumn, UpdateColumns, it works like Update, Updates


db.Model(&user).UpdateColumn("name", "hello")



db.Model(&user).UpdateColumns(User{Name: "hello", Age: 18})



db.Model(&user).Select("name", "age").UpdateColumns(User{Name: "hello", Age: 0})

Returning Data From Modified Rows

Returning changed data only works for databases which support Returning, for example:


var users []User
db.Model(&users).Clauses(clause.Returning{}).Where("role = ?", "admin").Update("salary", gorm.Expr("salary * ?", 2))




db.Model(&users).Clauses(clause.Returning{Columns: []clause.Column{{Name: "name"}, {Name: "salary"}}}).Where("role = ?", "admin").Update("salary", gorm.Expr("salary * ?", 2))

Check Field has changed?

GORM provides the Changed method which could be used in Before Update Hooks, it will return whether the field has changed or not.

The Changed method only works with methods Update, Updates, and it only checks if the updating value from Update / Updates equals the model value. It will return true if it is changed and not omitted

func (u *User) BeforeUpdate(tx *gorm.DB) (err error) {
  
  if tx.Statement.Changed("Role") {
    return errors.New("role not allowed to change")
  }

  if tx.Statement.Changed("Name", "Admin") { 
    tx.Statement.SetColumn("Age", 18)
  }

  
  if tx.Statement.Changed() {
    tx.Statement.SetColumn("RefreshedAt", time.Now())
  }
  return nil
}

db.Model(&User{ID: 1, Name: "jinzhu"}).Updates(map[string]interface{"name": "jinzhu2"})

db.Model(&User{ID: 1, Name: "jinzhu"}).Updates(map[string]interface{"name": "jinzhu"})

db.Model(&User{ID: 1, Name: "jinzhu"}).Select("Admin").Updates(map[string]interface{
  "name": "jinzhu2", "admin": false,
})


db.Model(&User{ID: 1, Name: "jinzhu"}).Updates(User{Name: "jinzhu2"})

db.Model(&User{ID: 1, Name: "jinzhu"}).Updates(User{Name: "jinzhu"})

db.Model(&User{ID: 1, Name: "jinzhu"}).Select("Admin").Updates(User{Name: "jinzhu2"})

Change Updating Values

To change updating values in Before Hooks, you should use SetColumn unless it is a full update with Save, for example:

func (user *User) BeforeSave(tx *gorm.DB) (err error) {
  if pw, err := bcrypt.GenerateFromPassword(user.Password, 0); err == nil {
    tx.Statement.SetColumn("EncryptedPassword", pw)
  }

  if tx.Statement.Changed("Code") {
    user.Age += 20
    tx.Statement.SetColumn("Age", user.Age)
  }
}

db.Model(&user).Update("Name", "jinzhu")

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