Esempio n. 1
0
 /** split predicates by AND op */
 public static List<ExprNodeDesc> split(ExprNodeDesc current, List<ExprNodeDesc> splitted) {
   if (FunctionRegistry.isOpAnd(current)) {
     for (ExprNodeDesc child : current.getChildren()) {
       split(child, splitted);
     }
     return splitted;
   }
   if (indexOf(current, splitted) < 0) {
     splitted.add(current);
   }
   return splitted;
 }
    @Override
    public Object process(
        Node nd, Stack<Node> stack, NodeProcessorCtx procCtx, Object... nodeOutputs)
        throws SemanticException {
      @SuppressWarnings("unchecked")
      CommonJoinOperator<JoinDesc> join = (CommonJoinOperator) nd;
      ReduceSinkOperator source = (ReduceSinkOperator) stack.get(stack.size() - 2);
      FilterOperator filter = (FilterOperator) stack.get(stack.size() - 3);
      int srcPos = join.getParentOperators().indexOf(source);

      TransitiveContext context = (TransitiveContext) procCtx;
      Map<CommonJoinOperator, int[][]> filterPropagates = context.getFilterPropagates();
      Map<ReduceSinkOperator, List<ExprNodeDesc>> newFilters = context.getNewfilters();

      int[][] targets = filterPropagates.get(join);
      if (targets == null) {
        filterPropagates.put(join, targets = getTargets(join));
      }

      List<Operator<? extends OperatorDesc>> parents = join.getParentOperators();
      for (int targetPos : targets[srcPos]) {
        ReduceSinkOperator target = (ReduceSinkOperator) parents.get(targetPos);
        List<ExprNodeDesc> sourceKeys = source.getConf().getKeyCols();
        List<ExprNodeDesc> targetKeys = target.getConf().getKeyCols();

        ExprNodeDesc predicate = filter.getConf().getPredicate();
        ExprNodeDesc replaced = ExprNodeDescUtils.replace(predicate, sourceKeys, targetKeys);
        if (replaced != null && !filterExists(target, replaced)) {
          List<ExprNodeDesc> prev = newFilters.get(target);
          if (prev == null) {
            newFilters.put(target, ExprNodeDescUtils.split(replaced));
          } else {
            ExprNodeDescUtils.split(replaced, prev);
          }
        }
      }
      return null;
    }
  @Override
  public ParseContext transform(ParseContext pctx) throws SemanticException {
    pGraphContext = pctx;

    Map<Rule, NodeProcessor> opRules = new LinkedHashMap<Rule, NodeProcessor>();
    opRules.put(
        new RuleRegExp(
            "R1",
            "("
                + FilterOperator.getOperatorName()
                + "%"
                + ReduceSinkOperator.getOperatorName()
                + "%"
                + JoinOperator.getOperatorName()
                + "%)"),
        new JoinTransitive());

    // The dispatcher fires the processor corresponding to the closest matching
    // rule and passes the context along
    TransitiveContext context = new TransitiveContext();
    Dispatcher disp = new DefaultRuleDispatcher(null, opRules, context);
    GraphWalker ogw = new LevelOrderWalker(disp, 2);

    // Create a list of topop nodes
    List<Node> topNodes = new ArrayList<Node>();
    topNodes.addAll(pGraphContext.getTopOps().values());
    ogw.startWalking(topNodes, null);

    Map<ReduceSinkOperator, List<ExprNodeDesc>> newFilters = context.getNewfilters();

    // insert new filter between RS and parent of RS
    for (Map.Entry<ReduceSinkOperator, List<ExprNodeDesc>> entry : newFilters.entrySet()) {
      ReduceSinkOperator reducer = entry.getKey();
      Operator<?> parent = reducer.getParentOperators().get(0);

      List<ExprNodeDesc> exprs = entry.getValue();
      if (parent instanceof FilterOperator) {
        exprs = ExprNodeDescUtils.split(((FilterOperator) parent).getConf().getPredicate(), exprs);
        ExprNodeDesc merged = ExprNodeDescUtils.mergePredicates(exprs);
        ((FilterOperator) parent).getConf().setPredicate(merged);
      } else {
        ExprNodeDesc merged = ExprNodeDescUtils.mergePredicates(exprs);
        RowSchema parentRS = parent.getSchema();
        Operator<FilterDesc> newFilter = createFilter(reducer, parent, parentRS, merged);
      }
    }

    return pGraphContext;
  }