Examples with PartialMatch com.apple.foundationdb.record.query.plan.temp.PartialMatch used on opensource projects

Example 1 with PartialMatch

use of com.apple.foundationdb.record.query.plan.temp.PartialMatch in project fdb-record-layer by FoundationDB.

the class SelectExpression method compensate.

@Override
@SuppressWarnings({ "java:S135", "java:S1066" })
public Compensation compensate(@Nonnull final PartialMatch partialMatch, @Nonnull final Map<CorrelationIdentifier, ComparisonRange> boundParameterPrefixMap) {
    final Map<QueryPredicate, QueryPredicate> toBeReappliedPredicatesMap = Maps.newIdentityHashMap();
    final MatchInfo matchInfo = partialMatch.getMatchInfo();
    final PredicateMap predicateMap = matchInfo.getPredicateMap();
    // 
    // The partial match we are called with here has child matches that have compensations on their own.
    // Given a pair of these matches that we reach along two for each quantifiers (forming a join) we have to
    // apply both compensations. The compensation class has a union method to combine two compensations in an
    // optimal way. We need to fold over all those compensations to form one child compensation. The tree that
    // is formed by partial matches therefore collapses into a chain of compensations.
    // 
    final List<? extends Quantifier> quantifiers = getQuantifiers();
    final Compensation childCompensation = quantifiers.stream().filter(quantifier -> quantifier instanceof Quantifier.ForEach).flatMap(quantifier -> matchInfo.getChildPartialMatch(quantifier).map(childPartialMatch -> childPartialMatch.compensate(boundParameterPrefixMap)).map(Stream::of).orElse(Stream.empty())).reduce(Compensation.noCompensation(), Compensation::union);
    // 
    // The fact that we matched the partial match handed in must mean that the child compensation is not impossible.
    // 
    Verify.verify(!childCompensation.isImpossible());
    // 
    for (final QueryPredicate predicate : getPredicates()) {
        final Optional<PredicateMapping> predicateMappingOptional = predicateMap.getMappingOptional(predicate);
        Verify.verify(predicateMappingOptional.isPresent());
        final PredicateMapping predicateMapping = predicateMappingOptional.get();
        final Optional<QueryPredicate> reappliedPredicateOptional = predicateMapping.reapplyPredicateFunction().reapplyPredicateMaybe(matchInfo, boundParameterPrefixMap);
        reappliedPredicateOptional.ifPresent(reappliedPredicate -> toBeReappliedPredicatesMap.put(predicate, reappliedPredicate));
    }
    return Compensation.ofChildCompensationAndPredicateMap(childCompensation, toBeReappliedPredicatesMap, computeMappedQuantifiers(partialMatch), computeUnmatchedForEachQuantifiers(partialMatch));
}

Example 2 with PartialMatch

use of com.apple.foundationdb.record.query.plan.temp.PartialMatch in project fdb-record-layer by FoundationDB.

the class SelectExpression method subsumedBy.

@Nonnull
@Override
public Iterable<MatchInfo> subsumedBy(@Nonnull final RelationalExpression candidateExpression, @Nonnull final AliasMap aliasMap, @Nonnull final IdentityBiMap<Quantifier, PartialMatch> partialMatchMap) {
    // TODO This method should be simplified by adding some structure to it.
    final Collection<MatchInfo> matchInfos = PartialMatch.matchesFromMap(partialMatchMap);
    Verify.verify(this != candidateExpression);
    if (getClass() != candidateExpression.getClass()) {
        return ImmutableList.of();
    }
    final SelectExpression otherSelectExpression = (SelectExpression) candidateExpression;
    // merge parameter maps -- early out if a binding clashes
    final ImmutableList<Map<CorrelationIdentifier, ComparisonRange>> parameterBindingMaps = matchInfos.stream().map(MatchInfo::getParameterBindingMap).collect(ImmutableList.toImmutableList());
    final Optional<Map<CorrelationIdentifier, ComparisonRange>> mergedParameterBindingMapOptional = MatchInfo.tryMergeParameterBindings(parameterBindingMaps);
    if (!mergedParameterBindingMapOptional.isPresent()) {
        return ImmutableList.of();
    }
    final Map<CorrelationIdentifier, ComparisonRange> mergedParameterBindingMap = mergedParameterBindingMapOptional.get();
    final ImmutableSet.Builder<CorrelationIdentifier> matchedCorrelatedToBuilder = ImmutableSet.builder();
    // for-each quantifiers. Also keep track of all aliases the matched quantifiers are correlated to.
    for (final Quantifier quantifier : getQuantifiers()) {
        if (partialMatchMap.containsKeyUnwrapped(quantifier)) {
            if (quantifier instanceof Quantifier.ForEach) {
                // current quantifier is matched
                final PartialMatch childPartialMatch = Objects.requireNonNull(partialMatchMap.getUnwrapped(quantifier));
                if (!childPartialMatch.getQueryExpression().computeUnmatchedForEachQuantifiers(childPartialMatch).isEmpty()) {
                    return ImmutableList.of();
                }
            }
            matchedCorrelatedToBuilder.addAll(quantifier.getCorrelatedTo());
        }
    }
    for (final Value resultValue : getResultValues()) {
        matchedCorrelatedToBuilder.addAll(resultValue.getCorrelatedTo());
    }
    final ImmutableSet<CorrelationIdentifier> matchedCorrelatedTo = matchedCorrelatedToBuilder.build();
    if (getQuantifiers().stream().anyMatch(quantifier -> quantifier instanceof Quantifier.ForEach && !partialMatchMap.containsKeyUnwrapped(quantifier))) {
        return ImmutableList.of();
    }
    final boolean allNonMatchedQuantifiersIndependent = getQuantifiers().stream().filter(quantifier -> !partialMatchMap.containsKeyUnwrapped(quantifier)).noneMatch(quantifier -> matchedCorrelatedTo.contains(quantifier.getAlias()));
    if (!allNonMatchedQuantifiersIndependent) {
        return ImmutableList.of();
    }
    // Loop through all for each quantifiers on the other side to ensure that they are all matched.
    // If any are not matched we cannot establish a match at all.
    final boolean allOtherForEachQuantifiersMatched = otherSelectExpression.getQuantifiers().stream().filter(quantifier -> quantifier instanceof Quantifier.ForEach).allMatch(quantifier -> aliasMap.containsTarget(quantifier.getAlias()));
    // would help us here to make sure the additional non-matched quantifier is not eliminating records.
    if (!allOtherForEachQuantifiersMatched) {
        return ImmutableList.of();
    }
    // 
    // Map predicates on the query side to predicates on the candidate side. Record parameter bindings and/or
    // compensations for each mapped predicate.
    // A predicate on this side (the query side) can cause us to filter out rows, a mapped predicate (for that
    // predicate) can only filter out fewer rows which is correct and can be compensated for. The important part
    // is that we must not have predicates on the other (candidate) side at the end of this mapping process which
    // would mean that the candidate eliminates records that the query side may not eliminate. If we detect that
    // case we MUST not create a match.
    // 
    final ImmutableList.Builder<Iterable<PredicateMapping>> predicateMappingsBuilder = ImmutableList.builder();
    // 
    if (getPredicates().isEmpty()) {
        final boolean allNonFiltering = otherSelectExpression.getPredicates().stream().allMatch(queryPredicate -> queryPredicate instanceof Placeholder || queryPredicate.isTautology());
        if (allNonFiltering) {
            return MatchInfo.tryMerge(partialMatchMap, mergedParameterBindingMap, PredicateMap.empty()).map(ImmutableList::of).orElse(ImmutableList.of());
        } else {
            return ImmutableList.of();
        }
    }
    for (final QueryPredicate predicate : getPredicates()) {
        final Set<PredicateMapping> impliedMappingsForPredicate = predicate.findImpliedMappings(aliasMap, otherSelectExpression.getPredicates());
        predicateMappingsBuilder.add(impliedMappingsForPredicate);
    }
    // 
    // We now have a multimap from predicates on the query side to predicates on the candidate side. In the trivial
    // case this multimap only contains singular mappings for a query predicate. If it doesn't we need to enumerate
    // through their cross product exhaustively. Each complete and non-contradictory element of that cross product
    // can lead to a match.
    // 
    final EnumeratingIterable<PredicateMapping> crossedMappings = CrossProduct.crossProduct(predicateMappingsBuilder.build());
    return IterableHelpers.flatMap(crossedMappings, predicateMappings -> {
        final Set<QueryPredicate> unmappedOtherPredicates = Sets.newIdentityHashSet();
        unmappedOtherPredicates.addAll(otherSelectExpression.getPredicates());
        final Map<CorrelationIdentifier, ComparisonRange> parameterBindingMap = Maps.newHashMap();
        final PredicateMap.Builder predicateMapBuilder = PredicateMap.builder();
        for (final PredicateMapping predicateMapping : predicateMappings) {
            predicateMapBuilder.put(predicateMapping.getQueryPredicate(), predicateMapping);
            unmappedOtherPredicates.remove(predicateMapping.getCandidatePredicate());
            final Optional<CorrelationIdentifier> parameterAliasOptional = predicateMapping.getParameterAliasOptional();
            final Optional<ComparisonRange> comparisonRangeOptional = predicateMapping.getComparisonRangeOptional();
            if (parameterAliasOptional.isPresent() && comparisonRangeOptional.isPresent()) {
                parameterBindingMap.put(parameterAliasOptional.get(), comparisonRangeOptional.get());
            }
        }
        // 
        // Last chance for unmapped predicates - if there is a placeholder or a tautology on the other side that is still
        // unmapped, we can (and should) remove it from the unmapped other set now. The reasoning is that this predicate is
        // not filtering so it does not cause records to be filtered that are not filtered on the query side.
        // 
        unmappedOtherPredicates.removeIf(queryPredicate -> queryPredicate instanceof Placeholder || queryPredicate.isTautology());
        if (!unmappedOtherPredicates.isEmpty()) {
            return ImmutableList.of();
        }
        final Optional<? extends PredicateMap> predicateMapOptional = predicateMapBuilder.buildMaybe();
        return predicateMapOptional.map(predicateMap -> {
            final Optional<Map<CorrelationIdentifier, ComparisonRange>> allParameterBindingMapOptional = MatchInfo.tryMergeParameterBindings(ImmutableList.of(mergedParameterBindingMap, parameterBindingMap));
            return allParameterBindingMapOptional.flatMap(allParameterBindingMap -> MatchInfo.tryMerge(partialMatchMap, allParameterBindingMap, predicateMap)).map(ImmutableList::of).orElse(ImmutableList.of());
        }).orElse(ImmutableList.of());
    });
}

Example 3 with PartialMatch

use of com.apple.foundationdb.record.query.plan.temp.PartialMatch in project fdb-record-layer by FoundationDB.

the class PlannerGraphProperty method show.

/**
 * Show the planner expression that and all the match candidates rendered in your default browser. This also
 * shows {@link PartialMatch}es between references if they exist.
 * @param renderSingleGroups iff true group references with just one member are not rendered
 * @param queryPlanRootReference the planner expression to be rendered.
 * @param matchCandidates a set of candidates for matching which should also be shown
 * @return the word "done" (IntelliJ really likes a return of String).
 */
@Nonnull
public static String show(final boolean renderSingleGroups, @Nonnull final GroupExpressionRef<? extends RelationalExpression> queryPlanRootReference, @Nonnull final Set<MatchCandidate> matchCandidates) {
    final PlannerGraph queryPlannerGraph = Objects.requireNonNull(queryPlanRootReference.acceptPropertyVisitor(forInternalShow(renderSingleGroups, true)));
    final PlannerGraph.InternalPlannerGraphBuilder graphBuilder = queryPlannerGraph.derived();
    final Map<MatchCandidate, PlannerGraph> matchCandidateMap = matchCandidates.stream().collect(ImmutableMap.toImmutableMap(Function.identity(), matchCandidate -> Objects.requireNonNull(matchCandidate.getTraversal().getRootReference().acceptPropertyVisitor(forInternalShow(renderSingleGroups)))));
    matchCandidateMap.forEach((matchCandidate, matchCandidateGraph) -> graphBuilder.addGraph(matchCandidateGraph));
    final ExpressionRefTraversal queryGraphTraversal = ExpressionRefTraversal.withRoot(queryPlanRootReference);
    final Set<ExpressionRef<? extends RelationalExpression>> queryGraphRefs = queryGraphTraversal.getRefs();
    queryGraphRefs.forEach(queryGraphRef -> {
        for (final MatchCandidate matchCandidate : Sets.intersection(matchCandidates, queryGraphRef.getMatchCandidates())) {
            final Set<PartialMatch> partialMatchesForCandidate = queryGraphRef.getPartialMatchesForCandidate(matchCandidate);
            final PlannerGraph matchCandidatePlannerGraph = Objects.requireNonNull(matchCandidateMap.get(matchCandidate));
            final Node queryRefNode = Objects.requireNonNull(queryPlannerGraph.getNodeForIdentity(queryGraphRef));
            for (final PartialMatch partialMatchForCandidate : partialMatchesForCandidate) {
                @Nullable final Node matchCandidateNode = matchCandidatePlannerGraph.getNodeForIdentity(partialMatchForCandidate.getCandidateRef());
                // should always be true but we don't want to bail out for corrupt graphs
                if (matchCandidateNode != null) {
                    graphBuilder.addEdge(queryRefNode, matchCandidateNode, new PartialMatchEdge());
                }
            }
        }
    });
    final String dotString = exportToDot(graphBuilder.build(), queryPlannerGraph.getNetwork().nodes(), nestedClusterProvider -> matchCandidateMap.entrySet().stream().map(entry -> new NamedCluster(entry.getKey().getName(), entry.getValue().getNetwork().nodes(), nestedClusterProvider)).collect(Collectors.toList()));
    return show(dotString);
}

Example 4 with PartialMatch

use of com.apple.foundationdb.record.query.plan.temp.PartialMatch in project fdb-record-layer by FoundationDB.

the class AdjustMatchRule method onMatch.

@Override
@SuppressWarnings("java:S135")
public void onMatch(@Nonnull PlannerRuleCall call) {
    final PlannerBindings bindings = call.getBindings();
    final PartialMatch incompleteMatch = bindings.get(rootMatcher);
    final ExpressionRef<? extends RelationalExpression> queryReference = incompleteMatch.getQueryRef();
    final MatchCandidate matchCandidate = incompleteMatch.getMatchCandidate();
    final SetMultimap<ExpressionRef<? extends RelationalExpression>, RelationalExpression> refToExpressionMap = matchCandidate.findReferencingExpressions(ImmutableList.of(queryReference));
    for (final Map.Entry<ExpressionRef<? extends RelationalExpression>, RelationalExpression> entry : refToExpressionMap.entries()) {
        final ExpressionRef<? extends RelationalExpression> candidateReference = entry.getKey();
        final RelationalExpression candidateExpression = entry.getValue();
        matchWithCandidate(incompleteMatch, candidateExpression).ifPresent(matchInfo -> call.yieldPartialMatch(incompleteMatch.getBoundAliasMap(), matchCandidate, incompleteMatch.getQueryExpression(), candidateReference, matchInfo));
    }
}

Example 5 with PartialMatch

use of com.apple.foundationdb.record.query.plan.temp.PartialMatch in project fdb-record-layer by FoundationDB.

the class AbstractDataAccessRule method maximumCoverageMatches.

/**
 * Private helper method to eliminate {@link PartialMatch}es whose coverage is entirely contained in other matches
 * (among the matches given).
 * @param matches candidate matches
 * @param interestedOrderings a set of interesting orderings
 * @return a list of {@link PartialMatch}es that are the maximum coverage matches among the matches handed in
 */
@Nonnull
@SuppressWarnings({ "java:S1905", "java:S135" })
private static List<PartialMatch> maximumCoverageMatches(@Nonnull final Collection<PartialMatch> matches, @Nonnull final Set<RequestedOrdering> interestedOrderings) {
    final ImmutableList<Pair<PartialMatch, Map<QueryPredicate, BoundKeyPart>>> boundKeyPartMapsForMatches = matches.stream().filter(partialMatch -> !satisfiedOrderings(partialMatch, interestedOrderings).isEmpty()).map(partialMatch -> Pair.of(partialMatch, computeBoundKeyPartMap(partialMatch))).sorted(Comparator.comparing((Function<Pair<PartialMatch, Map<QueryPredicate, BoundKeyPart>>, Integer>) p -> p.getValue().size()).reversed()).collect(ImmutableList.toImmutableList());
    final ImmutableList.Builder<PartialMatch> maximumCoverageMatchesBuilder = ImmutableList.builder();
    for (int i = 0; i < boundKeyPartMapsForMatches.size(); i++) {
        final PartialMatch outerMatch = boundKeyPartMapsForMatches.get(i).getKey();
        final Map<QueryPredicate, BoundKeyPart> outer = boundKeyPartMapsForMatches.get(i).getValue();
        boolean foundContainingInner = false;
        for (int j = 0; j < boundKeyPartMapsForMatches.size(); j++) {
            final Map<QueryPredicate, BoundKeyPart> inner = boundKeyPartMapsForMatches.get(j).getValue();
            // check if outer is completely contained in inner
            if (outer.size() >= inner.size()) {
                break;
            }
            if (i != j) {
                final boolean allContained = outer.entrySet().stream().allMatch(outerEntry -> inner.containsKey(outerEntry.getKey()));
                if (allContained) {
                    foundContainingInner = true;
                    break;
                }
            }
        }
        if (!foundContainingInner) {
            // 
            // no other partial match completely contained this one
            // 
            maximumCoverageMatchesBuilder.add(outerMatch);
        }
    }
    return maximumCoverageMatchesBuilder.build();
}