code: func (tx *Tx) QueryRowxContext(ctx context.Context, query string, args ...interface{}) *Row {
  	rows, err := tx.Tx.QueryContext(ctx, query, args...)
  	return &Row{rows: rows, err: err, unsafe: tx.unsafe, Mapper: tx.Mapper}
  }
docs: // QueryRowxContext within a transaction and context.
  // Any placeholder parameters are replaced with supplied args.