code: func PgRelkind(relType internal.RelType) string {
  	var s string
  	switch relType {
  	case internal.Table:
  		s = "r"
  	case internal.View:
  		s = "v"
  	default:
  		panic("unsupported RelType")
  	}
  	return s
  }
docs: // PgRelkind returns the postgres string representation for RelType.