code: func NewErr(errCode uint16, args ...interface{}) *SQLError {
  	e := &SQLError{Code: errCode}
  
  	if s, ok := MySQLState[errCode]; ok {
  		e.State = s
  	} else {
  		e.State = DefaultMySQLState
  	}
  
  	if format, ok := MySQLErrName[errCode]; ok {
  		e.Message = fmt.Sprintf(format, args...)
  	} else {
  		e.Message = fmt.Sprint(args...)
  	}
  
  	return e
  }
docs: // NewErr generates a SQL error, with an error code and default format specifier defined in MySQLErrName.