db.Mux.Unlock()

	// prepare completed
	defer close(cacheStmt.prepared)

	// Reason why cannot lock conn.PrepareContext
	// suppose the maxopen is 1, g1 is creating record and g2 is querying record.
	// 1. g1 begin tx, g1 is requeue because of waiting for the system call, now `db.ConnPool` db.numOpen == 1.
	// 2. g2 select lock `conn.PrepareContext(ctx, query)`, now db.numOpen == db.maxOpen , wait for release.

	}
	if len(config.UpdateClauses) == 0 {
		config.UpdateClauses = updateClauses
	}

	createCallback := db.Callback().Create()
	createCallback.Match(enableTransaction).Register("gorm:begin_transaction", BeginTransaction)
	createCallback.Register("gorm:before_create", BeforeCreate)
	createCallback.Register("gorm:save_before_associations", SaveBeforeAssociations(true))

	if err := DB.AutoMigrate(&Label{}, &Book{}); err != nil {
		t.Fatalf("failed to migrate, got %v", err)
	}

	book := Book{
		Name: "my book",
		Labels: []Label{
			{Name: "region", Value: "emea"},
		},
	}

	DB.Create(&book)

	var result Book
	if err := DB.Preload("Labels").First(&result, book.ID).Error; err != nil {
		t.Fatalf("failed to preload, got error %v", err)
	}

				},
			},
		},
	}

	DB.Create(&users)

	query := make([]string, 0)
	sess := DB.Session(&gorm.Session{Logger: Tracer{
		Logger: DB.Config.Logger,
		Test: func(ctx context.Context, begin time.Time, fc func() (sql string, rowsAffected int64), err error) {
			sql, _ := fc()
			query = append(query, sql)
		},
	}})

	var result []User
	err := sess.
		Joins("Manager").

	}
	if err := DB.Migrator().DropTable(&Organization{}, &Region{}); err != nil {
		t.Fatalf("Failed to migrate, got error: %s", err)
	}
	if err := DB.AutoMigrate(&Organization{}, &Region{}); err != nil {
		t.Fatalf("Failed to migrate, got error: %v", err)
	}
	region := &Region{Name: "Region1"}
	if err := DB.Create(region).Error; err != nil {
		t.Fatalf("fail to create region %v", err)
	}
	var orgs []Organization