Examples with DrillWindowRel org.apache.drill.exec.planner.logical.DrillWindowRel used on opensource projects

Example 1 with DrillWindowRel

use of org.apache.drill.exec.planner.logical.DrillWindowRel in project drill by apache.

the class WindowPrule method onMatch.

@Override
public void onMatch(RelOptRuleCall call) {
    final DrillWindowRel window = call.rel(0);
    RelNode input = call.rel(1);
    // TODO: Order window based on existing partition by
    //input.getTraitSet().subsumes()
    boolean partitionby = false;
    boolean addMerge = false;
    // The start index of the constant fields of DrillWindowRel
    final int startConstantsIndex = window.getInput().getRowType().getFieldCount();
    int constantShiftIndex = 0;
    for (final Ord<Window.Group> w : Ord.zip(window.groups)) {
        Window.Group windowBase = w.getValue();
        RelTraitSet traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL);
        // For empty Over-Clause
        if (windowBase.keys.isEmpty() && windowBase.orderKeys.getFieldCollations().isEmpty()) {
            DrillDistributionTrait distEmptyKeys = new DrillDistributionTrait(DrillDistributionTrait.DistributionType.SINGLETON);
            traits = traits.plus(distEmptyKeys);
        } else if (windowBase.keys.size() > 0) {
            DrillDistributionTrait distOnAllKeys = new DrillDistributionTrait(DrillDistributionTrait.DistributionType.HASH_DISTRIBUTED, ImmutableList.copyOf(getDistributionFields(windowBase)));
            partitionby = true;
            traits = traits.plus(distOnAllKeys);
        } else if (windowBase.orderKeys.getFieldCollations().size() > 0) {
            // if only the order-by clause is specified, there is a single partition
            // consisting of all the rows, so we do a distributed sort followed by a
            // single merge as the input of the window operator
            DrillDistributionTrait distKeys = new DrillDistributionTrait(DrillDistributionTrait.DistributionType.HASH_DISTRIBUTED, ImmutableList.copyOf(getDistributionFieldsFromCollation(windowBase)));
            traits = traits.plus(distKeys);
            if (!isSingleMode(call)) {
                addMerge = true;
            }
        }
        // Add collation trait if either partition-by or order-by is specified.
        if (partitionby || windowBase.orderKeys.getFieldCollations().size() > 0) {
            RelCollation collation = getCollation(windowBase);
            traits = traits.plus(collation);
        }
        RelNode convertedInput = convert(input, traits);
        if (addMerge) {
            traits = traits.plus(DrillDistributionTrait.SINGLETON);
            convertedInput = new SingleMergeExchangePrel(window.getCluster(), traits, convertedInput, windowBase.collation());
        }
        List<RelDataTypeField> newRowFields = Lists.newArrayList();
        for (RelDataTypeField field : convertedInput.getRowType().getFieldList()) {
            newRowFields.add(field);
        }
        Iterable<RelDataTypeField> newWindowFields = Iterables.filter(window.getRowType().getFieldList(), new Predicate<RelDataTypeField>() {

            @Override
            public boolean apply(RelDataTypeField relDataTypeField) {
                return relDataTypeField.getName().startsWith("w" + w.i + "$");
            }
        });
        for (RelDataTypeField newField : newWindowFields) {
            newRowFields.add(newField);
        }
        RelDataType rowType = new RelRecordType(newRowFields);
        List<Window.RexWinAggCall> newWinAggCalls = Lists.newArrayList();
        for (Ord<Window.RexWinAggCall> aggOrd : Ord.zip(windowBase.aggCalls)) {
            Window.RexWinAggCall aggCall = aggOrd.getValue();
            // If the argument points at the constant and
            // additional fields have been generated by the Window below,
            // the index of constants will be shifted
            final List<RexNode> newOperandsOfWindowFunction = Lists.newArrayList();
            for (RexNode operand : aggCall.getOperands()) {
                if (operand instanceof RexInputRef) {
                    final RexInputRef rexInputRef = (RexInputRef) operand;
                    final int refIndex = rexInputRef.getIndex();
                    // Check if this RexInputRef points at the constants
                    if (rexInputRef.getIndex() >= startConstantsIndex) {
                        operand = new RexInputRef(refIndex + constantShiftIndex, window.constants.get(refIndex - startConstantsIndex).getType());
                    }
                }
                newOperandsOfWindowFunction.add(operand);
            }
            aggCall = new Window.RexWinAggCall((SqlAggFunction) aggCall.getOperator(), aggCall.getType(), newOperandsOfWindowFunction, aggCall.ordinal);
            newWinAggCalls.add(new Window.RexWinAggCall((SqlAggFunction) aggCall.getOperator(), aggCall.getType(), aggCall.getOperands(), aggOrd.i));
        }
        windowBase = new Window.Group(windowBase.keys, windowBase.isRows, windowBase.lowerBound, windowBase.upperBound, windowBase.orderKeys, newWinAggCalls);
        input = new WindowPrel(window.getCluster(), window.getTraitSet().merge(traits), convertedInput, window.getConstants(), rowType, windowBase);
        constantShiftIndex += windowBase.aggCalls.size();
    }
    call.transformTo(input);
}