nullStr     = "NULL"
)

func isPrintable(s string) bool {
	for _, r := range s {
		if !unicode.IsPrint(r) {
			return false
		}
	}
	return true
}

// A list of Go types that should be converted to SQL primitives
var convertibleTypes = []reflect.Type{reflect.TypeOf(time.Time{}), reflect.TypeOf(false), reflect.TypeOf([]byte{})}

// RegEx matches only numeric values
var numericPlaceholderRe = regexp.MustCompile(`\$\d+\$`)

}

// Apply update config to new config
func (c *Config) Apply(config *Config) error {
	if config != c {
		*config = *c
	}
	return nil
}

// AfterInitialize initialize plugins after db connected
func (c *Config) AfterInitialize(db *DB) error {
	if db != nil {
		for _, plugin := range c.Plugins {
			if err := plugin.Initialize(db); err != nil {
				return err
			}
		}
	}
	return nil
}

	TxCommitter
	StmtContext(ctx context.Context, stmt *sql.Stmt) *sql.Stmt
}

// Valuer gorm valuer interface
type Valuer interface {
	GormValue(context.Context, *DB) clause.Expr
}

// GetDBConnector SQL db connector
type GetDBConnector interface {
	GetDBConn() (*sql.DB, error)
}

// Rows rows interface
type Rows interface {
	Columns() ([]string, error)
	ColumnTypes() ([]*sql.ColumnType, error)
	Next() bool