// 3. g1 tx exec insert, wait for unlock `conn.PrepareContext(ctx, query)` to finish tx and release.
	stmt, err := conn.PrepareContext(ctx, query)
	if err != nil {
		cacheStmt.prepareErr = err
		db.Mux.Lock()
		delete(db.Stmts, query)
		db.Mux.Unlock()
		return Stmt{}, err
	}

	db.Mux.Lock()
	cacheStmt.Stmt = stmt
	db.PreparedSQL = append(db.PreparedSQL, query)

import (
	"reflect"

	"gorm.io/gorm"
)

func callMethod(db *gorm.DB, fc func(value interface{}, tx *gorm.DB) bool) {
	tx := db.Session(&gorm.Session{NewDB: true})
	if called := fc(db.Statement.ReflectValue.Interface(), tx); !called {
		switch db.Statement.ReflectValue.Kind() {
		case reflect.Slice, reflect.Array:
			db.Statement.CurDestIndex = 0
			for i := 0; i < db.Statement.ReflectValue.Len(); i++ {

	DB.Create(&user)

	// Update a single field of the user and verify that the changed address is not stored.
	newAge := uint(100)
	user.Account.Number = "new_account_number"
	db := DB.Model(&user).UpdateColumns(User{Age: newAge})

	if db.RowsAffected != 1 {
		t.Errorf("Expected RowsAffected=1 but instead RowsAffected=%v", db.RowsAffected)
	}

	// Verify that Age now=`newAge`.

	}
}

func TestTransactionOnClosedConn(t *testing.T) {
	DB, err := OpenTestConnection(&gorm.Config{})
	if err != nil {
		t.Fatalf("failed to connect database, got error %v", err)
	}
	rawDB, _ := DB.DB()
	rawDB.Close()

	if err := DB.Transaction(func(tx *gorm.DB) error {
		return nil
	}); err == nil {
		t.Errorf("should returns error when commit with closed conn, got error %v", err)
	}

)

func TestHasOneAssociation(t *testing.T) {
	user := *GetUser("hasone", Config{Account: true})

	if err := DB.Create(&user).Error; err != nil {
		t.Fatalf("errors happened when create: %v", err)
	}

	CheckUser(t, user, user)

	// Find
	var user2 User
	DB.Find(&user2, "id = ?", user.ID)
	DB.Model(&user2).Association("Account").Find(&user2.Account)
	CheckUser(t, user2, user)

	// Count

	person2 := Person{Name: "person 2"}
	DB.Save(&person1).Save(&person2)

	address1 := Address{Name: "address 1"}
	address2 := Address{Name: "address 2"}
	DB.Save(&address1).Save(&address2)

	DB.Create(&PersonAddress{PersonID: person1.ID, AddressID: int(address1.ID)})
	DB.Create(&PersonAddress{PersonID: person1.ID, AddressID: int(address2.ID)})
	DB.Create(&PersonAddress{PersonID: person2.ID, AddressID: int(address1.ID)})

	if err := DB.Create(&user).Error; err != nil {
		t.Fatalf("errors happened when create: %v", err)
	}

	user.Languages = []Language{{Code: "zh-CN", Name: "Chinese"}, {Code: "en", Name: "English"}}
	for _, lang := range user.Languages {
		DB.Create(&lang)
	}
	user.Friends = []*User{{Name: "friend-1"}, {Name: "friend-2"}}

	if err := DB.Save(&user).Error; err != nil {

	}

	var result2 ScannerValuerStruct
	if err := DB.First(&result2, result.ID).Error; err != nil {
		t.Errorf("got error %v when query with %v", err, result.ID)
	}

	AssertObjEqual(t, result2, result, "ID", "CreatedAt", "UpdatedAt", "Name", "Gender", "Age")
}

func TestInvalidValuer(t *testing.T) {
	DB.Migrator().DropTable(&ScannerValuerStruct{})
	if err := DB.Migrator().AutoMigrate(&ScannerValuerStruct{}); err != nil {

func isMysql() bool {
	return os.Getenv("GORM_DIALECT") == "mysql"
}

func isSqlite() bool {
	return os.Getenv("GORM_DIALECT") == "sqlite"
}

func db(unscoped bool) *gorm.DB {
	if unscoped {
		return DB.Unscoped()
	} else {
		return DB
	}

import (
	"reflect"
	"sync"
	"testing"

	"gorm.io/gorm"
	"gorm.io/gorm/schema"
)

type UserWithCallback struct{}

func (UserWithCallback) BeforeSave(*gorm.DB) error {
	return nil
}

func (UserWithCallback) AfterCreate(*gorm.DB) error {
	return nil
}

func TestCallback(t *testing.T) {
	user, err := schema.Parse(&UserWithCallback{}, &sync.Map{}, schema.NamingStrategy{})
	if err != nil {