docs: public static VoltTable unionTables(Collection<VoltTable> operands) {
          VoltTable result = null;
  
          // Locate the first non-null table to get the schema
          for (VoltTable vt : operands) {
              if (vt != null) {
                  result = new VoltTable(vt.getTableSchema());
                  result.setStatusCode(vt.getStatusCode());
                  break;
              }
          }
  
          if (result != null) {
              result.addTables(operands);
              result.resetRowPosition();
          }
  
          return result;
      }