Examples with RexCall org.apache.calcite.rex.RexCall used on opensource projects

Example 11 with RexCall

use of org.apache.calcite.rex.RexCall in project calcite by apache.

the class RexImpTable method createImplementor.

public static CallImplementor createImplementor(final NotNullImplementor implementor, final NullPolicy nullPolicy, final boolean harmonize) {
    switch(nullPolicy) {
        case ANY:
        case STRICT:
        case SEMI_STRICT:
            return new CallImplementor() {

                public Expression implement(RexToLixTranslator translator, RexCall call, NullAs nullAs) {
                    return implementNullSemantics0(translator, call, nullAs, nullPolicy, harmonize, implementor);
                }
            };
        case AND:
            // : Boolean.FALSE;
            return new CallImplementor() {

                public Expression implement(RexToLixTranslator translator, RexCall call, NullAs nullAs) {
                    assert call.getOperator() == AND : "AND null semantics is supported only for AND operator. Actual operator is " + String.valueOf(call.getOperator());
                    final RexCall call2 = call2(false, translator, call);
                    switch(nullAs) {
                        // Just foldAnd
                        case NOT_POSSIBLE:
                        case TRUE:
                        // thus if we convert nulls to true then no harm is made
                        case FALSE:
                            // AND call should return false iff has FALSEs or has NULLs,
                            // thus if we convert nulls to false, no harm is made
                            final List<Expression> expressions = translator.translateList(call2.getOperands(), nullAs);
                            return Expressions.foldAnd(expressions);
                        case NULL:
                        case IS_NULL:
                        case IS_NOT_NULL:
                            final List<Expression> nullAsTrue = translator.translateList(call2.getOperands(), NullAs.TRUE);
                            final List<Expression> nullAsIsNull = translator.translateList(call2.getOperands(), NullAs.IS_NULL);
                            Expression hasFalse = Expressions.not(Expressions.foldAnd(nullAsTrue));
                            Expression hasNull = Expressions.foldOr(nullAsIsNull);
                            Expression result = nullAs.handle(Expressions.condition(hasFalse, BOXED_FALSE_EXPR, Expressions.condition(hasNull, NULL_EXPR, BOXED_TRUE_EXPR)));
                            return result;
                        default:
                            throw new IllegalArgumentException("Unknown nullAs when implementing AND: " + nullAs);
                    }
                }
            };
        case OR:
            // : Boolean.TRUE;
            return new CallImplementor() {

                public Expression implement(RexToLixTranslator translator, RexCall call, final NullAs nullAs) {
                    assert call.getOperator() == OR : "OR null semantics is supported only for OR operator. Actual operator is " + String.valueOf(call.getOperator());
                    final RexCall call2 = call2(harmonize, translator, call);
                    switch(nullAs) {
                        // Just foldOr
                        case NOT_POSSIBLE:
                        case TRUE:
                        // thus we convert nulls to TRUE and foldOr
                        case FALSE:
                            // This should return true iff has TRUE arguments,
                            // thus we convert nulls to FALSE and foldOr
                            final List<Expression> expressions = translator.translateList(call2.getOperands(), nullAs);
                            return Expressions.foldOr(expressions);
                        case NULL:
                        case IS_NULL:
                        case IS_NOT_NULL:
                            final List<Expression> nullAsFalse = translator.translateList(call2.getOperands(), NullAs.FALSE);
                            final List<Expression> nullAsIsNull = translator.translateList(call2.getOperands(), NullAs.IS_NULL);
                            Expression hasTrue = Expressions.foldOr(nullAsFalse);
                            Expression hasNull = Expressions.foldOr(nullAsIsNull);
                            Expression result = nullAs.handle(Expressions.condition(hasTrue, BOXED_TRUE_EXPR, Expressions.condition(hasNull, NULL_EXPR, BOXED_FALSE_EXPR)));
                            return result;
                        default:
                            throw new IllegalArgumentException("Unknown nullAs when implementing OR: " + nullAs);
                    }
                }
            };
        case NOT:
            // else false.
            return new CallImplementor() {

                public Expression implement(RexToLixTranslator translator, RexCall call, NullAs nullAs) {
                    switch(nullAs) {
                        case NULL:
                            return Expressions.call(BuiltInMethod.NOT.method, translator.translateList(call.getOperands(), nullAs));
                        default:
                            return Expressions.not(translator.translate(call.getOperands().get(0), negate(nullAs)));
                    }
                }

                private NullAs negate(NullAs nullAs) {
                    switch(nullAs) {
                        case FALSE:
                            return NullAs.TRUE;
                        case TRUE:
                            return NullAs.FALSE;
                        default:
                            return nullAs;
                    }
                }
            };
        case NONE:
            return new CallImplementor() {

                public Expression implement(RexToLixTranslator translator, RexCall call, NullAs nullAs) {
                    final RexCall call2 = call2(false, translator, call);
                    return implementCall(translator, call2, implementor, nullAs);
                }
            };
        default:
            throw new AssertionError(nullPolicy);
    }
}

Example 12 with RexCall

use of org.apache.calcite.rex.RexCall in project calcite by apache.

the class RexToLixTranslator method translate0.

/**
 * Translates an expression that is not in the cache.
 *
 * @param expr Expression
 * @param nullAs If false, if expression is definitely not null at
 *   runtime. Therefore we can optimize. For example, we can cast to int
 *   using x.intValue().
 * @return Translated expression
 */
private Expression translate0(RexNode expr, RexImpTable.NullAs nullAs, Type storageType) {
    if (nullAs == RexImpTable.NullAs.NULL && !expr.getType().isNullable()) {
        nullAs = RexImpTable.NullAs.NOT_POSSIBLE;
    }
    switch(expr.getKind()) {
        case INPUT_REF:
            final int index = ((RexInputRef) expr).getIndex();
            Expression x = inputGetter.field(list, index, storageType);
            // safe to share
            Expression input = list.append("inp" + index + "_", x);
            if (nullAs == RexImpTable.NullAs.NOT_POSSIBLE && input.type.equals(storageType)) {
                // unboxing via nullAs.handle below.
                return input;
            }
            return handleNull(input, nullAs);
        case LOCAL_REF:
            return translate(deref(expr), nullAs, storageType);
        case LITERAL:
            return translateLiteral((RexLiteral) expr, nullifyType(expr.getType(), isNullable(expr) && nullAs != RexImpTable.NullAs.NOT_POSSIBLE), typeFactory, nullAs);
        case DYNAMIC_PARAM:
            return translateParameter((RexDynamicParam) expr, nullAs, storageType);
        case CORREL_VARIABLE:
            throw new RuntimeException("Cannot translate " + expr + ". Correlated" + " variables should always be referenced by field access");
        case FIELD_ACCESS:
            RexFieldAccess fieldAccess = (RexFieldAccess) expr;
            RexNode target = deref(fieldAccess.getReferenceExpr());
            // only $cor.field access is supported
            if (!(target instanceof RexCorrelVariable)) {
                throw new RuntimeException("cannot translate expression " + expr);
            }
            if (correlates == null) {
                throw new RuntimeException("Cannot translate " + expr + " since " + "correlate variables resolver is not defined");
            }
            InputGetter getter = correlates.apply(((RexCorrelVariable) target).getName());
            return getter.field(list, fieldAccess.getField().getIndex(), storageType);
        default:
            if (expr instanceof RexCall) {
                return translateCall((RexCall) expr, nullAs);
            }
            throw new RuntimeException("cannot translate expression " + expr);
    }
}

Example 13 with RexCall

use of org.apache.calcite.rex.RexCall in project calcite by apache.

the class EnumerableTableFunctionScan method isQueryable.

private boolean isQueryable() {
    if (!(getCall() instanceof RexCall)) {
        return false;
    }
    final RexCall call = (RexCall) getCall();
    if (!(call.getOperator() instanceof SqlUserDefinedTableFunction)) {
        return false;
    }
    final SqlUserDefinedTableFunction udtf = (SqlUserDefinedTableFunction) call.getOperator();
    if (!(udtf.getFunction() instanceof TableFunctionImpl)) {
        return false;
    }
    final TableFunctionImpl tableFunction = (TableFunctionImpl) udtf.getFunction();
    final Method method = tableFunction.method;
    return QueryableTable.class.isAssignableFrom(method.getReturnType());
}

Example 14 with RexCall

use of org.apache.calcite.rex.RexCall in project calcite by apache.

the class AbstractMaterializedViewRule method replaceWithOriginalReferences.

/**
 * Given the input expression, it will replace (sub)expressions when possible
 * using the content of the mapping. In particular, the mapping contains the
 * digest of the expression and the index that the replacement input ref should
 * point to.
 */
private static RexNode replaceWithOriginalReferences(final RexBuilder rexBuilder, final RelNode node, final NodeLineage nodeLineage, final RexNode exprToRewrite) {
    // Currently we allow the following:
    // 1) compensation pred can be directly map to expression
    // 2) all references in compensation pred can be map to expressions
    // We support bypassing lossless casts.
    RexShuttle visitor = new RexShuttle() {

        @Override
        public RexNode visitCall(RexCall call) {
            RexNode rw = replace(call);
            return rw != null ? rw : super.visitCall(call);
        }

        @Override
        public RexNode visitTableInputRef(RexTableInputRef inputRef) {
            RexNode rw = replace(inputRef);
            return rw != null ? rw : super.visitTableInputRef(inputRef);
        }

        private RexNode replace(RexNode e) {
            Integer pos = nodeLineage.exprsLineage.get(e.toString());
            if (pos != null) {
                // Found it
                return rexBuilder.makeInputRef(node, pos);
            }
            pos = nodeLineage.exprsLineageLosslessCasts.get(e.toString());
            if (pos != null) {
                // Found it
                return rexBuilder.makeCast(e.getType(), rexBuilder.makeInputRef(node, pos));
            }
            return null;
        }
    };
    return visitor.apply(exprToRewrite);
}

Example 15 with RexCall

use of org.apache.calcite.rex.RexCall in project calcite by apache.

the class AbstractMaterializedViewRule method perform.

/**
 * Rewriting logic is based on "Optimizing Queries Using Materialized Views:
 * A Practical, Scalable Solution" by Goldstein and Larson.
 *
 * <p>On the query side, rules matches a Project-node chain or node, where node
 * is either an Aggregate or a Join. Subplan rooted at the node operator must
 * be composed of one or more of the following operators: TableScan, Project,
 * Filter, and Join.
 *
 * <p>For each join MV, we need to check the following:
 * <ol>
 * <li> The plan rooted at the Join operator in the view produces all rows
 * needed by the plan rooted at the Join operator in the query.</li>
 * <li> All columns required by compensating predicates, i.e., predicates that
 * need to be enforced over the view, are available at the view output.</li>
 * <li> All output expressions can be computed from the output of the view.</li>
 * <li> All output rows occur with the correct duplication factor. We might
 * rely on existing Unique-Key - Foreign-Key relationships to extract that
 * information.</li>
 * </ol>
 *
 * <p>In turn, for each aggregate MV, we need to check the following:
 * <ol>
 * <li> The plan rooted at the Aggregate operator in the view produces all rows
 * needed by the plan rooted at the Aggregate operator in the query.</li>
 * <li> All columns required by compensating predicates, i.e., predicates that
 * need to be enforced over the view, are available at the view output.</li>
 * <li> The grouping columns in the query are a subset of the grouping columns
 * in the view.</li>
 * <li> All columns required to perform further grouping are available in the
 * view output.</li>
 * <li> All columns required to compute output expressions are available in the
 * view output.</li>
 * </ol>
 *
 * <p>The rule contains multiple extensions compared to the original paper. One of
 * them is the possibility of creating rewritings using Union operators, e.g., if
 * the result of a query is partially contained in the materialized view.
 */
protected void perform(RelOptRuleCall call, Project topProject, RelNode node) {
    final RexBuilder rexBuilder = node.getCluster().getRexBuilder();
    final RelMetadataQuery mq = RelMetadataQuery.instance();
    final RelOptPlanner planner = call.getPlanner();
    final RexExecutor executor = Util.first(planner.getExecutor(), RexUtil.EXECUTOR);
    final RelOptPredicateList predicates = RelOptPredicateList.EMPTY;
    final RexSimplify simplify = new RexSimplify(rexBuilder, predicates, true, executor);
    final List<RelOptMaterialization> materializations = (planner instanceof VolcanoPlanner) ? ((VolcanoPlanner) planner).getMaterializations() : ImmutableList.<RelOptMaterialization>of();
    if (!materializations.isEmpty()) {
        // try to generate a rewriting are met
        if (!isValidPlan(topProject, node, mq)) {
            return;
        }
        // Obtain applicable (filtered) materializations
        // TODO: Filtering of relevant materializations needs to be
        // improved so we gather only materializations that might
        // actually generate a valid rewriting.
        final List<RelOptMaterialization> applicableMaterializations = RelOptMaterializations.getApplicableMaterializations(node, materializations);
        if (!applicableMaterializations.isEmpty()) {
            // 2. Initialize all query related auxiliary data structures
            // that will be used throughout query rewriting process
            // Generate query table references
            final Set<RelTableRef> queryTableRefs = mq.getTableReferences(node);
            if (queryTableRefs == null) {
                // Bail out
                return;
            }
            // Extract query predicates
            final RelOptPredicateList queryPredicateList = mq.getAllPredicates(node);
            if (queryPredicateList == null) {
                // Bail out
                return;
            }
            final RexNode pred = simplify.simplify(RexUtil.composeConjunction(rexBuilder, queryPredicateList.pulledUpPredicates, false));
            final Triple<RexNode, RexNode, RexNode> queryPreds = splitPredicates(rexBuilder, pred);
            // Extract query equivalence classes. An equivalence class is a set
            // of columns in the query output that are known to be equal.
            final EquivalenceClasses qEC = new EquivalenceClasses();
            for (RexNode conj : RelOptUtil.conjunctions(queryPreds.getLeft())) {
                assert conj.isA(SqlKind.EQUALS);
                RexCall equiCond = (RexCall) conj;
                qEC.addEquivalenceClass((RexTableInputRef) equiCond.getOperands().get(0), (RexTableInputRef) equiCond.getOperands().get(1));
            }
            // rewrite the given query
            for (RelOptMaterialization materialization : applicableMaterializations) {
                RelNode view = materialization.tableRel;
                Project topViewProject;
                RelNode viewNode;
                if (materialization.queryRel instanceof Project) {
                    topViewProject = (Project) materialization.queryRel;
                    viewNode = topViewProject.getInput();
                } else {
                    topViewProject = null;
                    viewNode = materialization.queryRel;
                }
                // 3.1. View checks before proceeding
                if (!isValidPlan(topViewProject, viewNode, mq)) {
                    // Skip it
                    continue;
                }
                // 3.2. Initialize all query related auxiliary data structures
                // that will be used throughout query rewriting process
                // Extract view predicates
                final RelOptPredicateList viewPredicateList = mq.getAllPredicates(viewNode);
                if (viewPredicateList == null) {
                    // Skip it
                    continue;
                }
                final RexNode viewPred = simplify.simplify(RexUtil.composeConjunction(rexBuilder, viewPredicateList.pulledUpPredicates, false));
                final Triple<RexNode, RexNode, RexNode> viewPreds = splitPredicates(rexBuilder, viewPred);
                // Extract view table references
                final Set<RelTableRef> viewTableRefs = mq.getTableReferences(viewNode);
                if (viewTableRefs == null) {
                    // Bail out
                    return;
                }
                // Extract view tables
                MatchModality matchModality;
                Multimap<RexTableInputRef, RexTableInputRef> compensationEquiColumns = ArrayListMultimap.create();
                if (!queryTableRefs.equals(viewTableRefs)) {
                    // subset of query tables (add additional tables through joins if possible)
                    if (viewTableRefs.containsAll(queryTableRefs)) {
                        matchModality = MatchModality.QUERY_PARTIAL;
                        final EquivalenceClasses vEC = new EquivalenceClasses();
                        for (RexNode conj : RelOptUtil.conjunctions(viewPreds.getLeft())) {
                            assert conj.isA(SqlKind.EQUALS);
                            RexCall equiCond = (RexCall) conj;
                            vEC.addEquivalenceClass((RexTableInputRef) equiCond.getOperands().get(0), (RexTableInputRef) equiCond.getOperands().get(1));
                        }
                        if (!compensatePartial(viewTableRefs, vEC, queryTableRefs, compensationEquiColumns)) {
                            // Cannot rewrite, skip it
                            continue;
                        }
                    } else if (queryTableRefs.containsAll(viewTableRefs)) {
                        matchModality = MatchModality.VIEW_PARTIAL;
                        ViewPartialRewriting partialRewritingResult = compensateViewPartial(call.builder(), rexBuilder, mq, view, topProject, node, queryTableRefs, qEC, topViewProject, viewNode, viewTableRefs);
                        if (partialRewritingResult == null) {
                            // Cannot rewrite, skip it
                            continue;
                        }
                        // Rewrite succeeded
                        view = partialRewritingResult.newView;
                        topViewProject = partialRewritingResult.newTopViewProject;
                        viewNode = partialRewritingResult.newViewNode;
                    } else {
                        // Skip it
                        continue;
                    }
                } else {
                    matchModality = MatchModality.COMPLETE;
                }
                // 4. We map every table in the query to a table with the same qualified
                // name (all query tables are contained in the view, thus this is equivalent
                // to mapping every table in the query to a view table).
                final Multimap<RelTableRef, RelTableRef> multiMapTables = ArrayListMultimap.create();
                for (RelTableRef queryTableRef1 : queryTableRefs) {
                    for (RelTableRef queryTableRef2 : queryTableRefs) {
                        if (queryTableRef1.getQualifiedName().equals(queryTableRef2.getQualifiedName())) {
                            multiMapTables.put(queryTableRef1, queryTableRef2);
                        }
                    }
                }
                // If a table is used multiple times, we will create multiple mappings,
                // and we will try to rewrite the query using each of the mappings.
                // Then, we will try to map every source table (query) to a target
                // table (view), and if we are successful, we will try to create
                // compensation predicates to filter the view results further
                // (if needed).
                final List<BiMap<RelTableRef, RelTableRef>> flatListMappings = generateTableMappings(multiMapTables);
                for (BiMap<RelTableRef, RelTableRef> queryToViewTableMapping : flatListMappings) {
                    // TableMapping : mapping query tables -> view tables
                    // 4.0. If compensation equivalence classes exist, we need to add
                    // the mapping to the query mapping
                    final EquivalenceClasses currQEC = EquivalenceClasses.copy(qEC);
                    if (matchModality == MatchModality.QUERY_PARTIAL) {
                        for (Entry<RexTableInputRef, RexTableInputRef> e : compensationEquiColumns.entries()) {
                            // Copy origin
                            RelTableRef queryTableRef = queryToViewTableMapping.inverse().get(e.getKey().getTableRef());
                            RexTableInputRef queryColumnRef = RexTableInputRef.of(queryTableRef, e.getKey().getIndex(), e.getKey().getType());
                            // Add to query equivalence classes and table mapping
                            currQEC.addEquivalenceClass(queryColumnRef, e.getValue());
                            queryToViewTableMapping.put(e.getValue().getTableRef(), // identity
                            e.getValue().getTableRef());
                        }
                    }
                    // 4.1. Compute compensation predicates, i.e., predicates that need to be
                    // enforced over the view to retain query semantics. The resulting predicates
                    // are expressed using {@link RexTableInputRef} over the query.
                    // First, to establish relationship, we swap column references of the view
                    // predicates to point to query tables and compute equivalence classes.
                    final RexNode viewColumnsEquiPred = RexUtil.swapTableReferences(rexBuilder, viewPreds.getLeft(), queryToViewTableMapping.inverse());
                    final EquivalenceClasses queryBasedVEC = new EquivalenceClasses();
                    for (RexNode conj : RelOptUtil.conjunctions(viewColumnsEquiPred)) {
                        assert conj.isA(SqlKind.EQUALS);
                        RexCall equiCond = (RexCall) conj;
                        queryBasedVEC.addEquivalenceClass((RexTableInputRef) equiCond.getOperands().get(0), (RexTableInputRef) equiCond.getOperands().get(1));
                    }
                    Triple<RexNode, RexNode, RexNode> compensationPreds = computeCompensationPredicates(rexBuilder, simplify, currQEC, queryPreds, queryBasedVEC, viewPreds, queryToViewTableMapping);
                    if (compensationPreds == null && generateUnionRewriting) {
                        // Attempt partial rewriting using union operator. This rewriting
                        // will read some data from the view and the rest of the data from
                        // the query computation. The resulting predicates are expressed
                        // using {@link RexTableInputRef} over the view.
                        compensationPreds = computeCompensationPredicates(rexBuilder, simplify, queryBasedVEC, viewPreds, currQEC, queryPreds, queryToViewTableMapping.inverse());
                        if (compensationPreds == null) {
                            // This was our last chance to use the view, skip it
                            continue;
                        }
                        RexNode compensationColumnsEquiPred = compensationPreds.getLeft();
                        RexNode otherCompensationPred = RexUtil.composeConjunction(rexBuilder, ImmutableList.of(compensationPreds.getMiddle(), compensationPreds.getRight()), false);
                        assert !compensationColumnsEquiPred.isAlwaysTrue() || !otherCompensationPred.isAlwaysTrue();
                        // b. Generate union branch (query).
                        final RelNode unionInputQuery = rewriteQuery(call.builder(), rexBuilder, simplify, mq, compensationColumnsEquiPred, otherCompensationPred, topProject, node, queryToViewTableMapping, queryBasedVEC, currQEC);
                        if (unionInputQuery == null) {
                            // Skip it
                            continue;
                        }
                        // c. Generate union branch (view).
                        // We trigger the unifying method. This method will either create a Project
                        // or an Aggregate operator on top of the view. It will also compute the
                        // output expressions for the query.
                        final RelNode unionInputView = rewriteView(call.builder(), rexBuilder, simplify, mq, matchModality, true, view, topProject, node, topViewProject, viewNode, queryToViewTableMapping, currQEC);
                        if (unionInputView == null) {
                            // Skip it
                            continue;
                        }
                        // d. Generate final rewriting (union).
                        final RelNode result = createUnion(call.builder(), rexBuilder, topProject, unionInputQuery, unionInputView);
                        if (result == null) {
                            // Skip it
                            continue;
                        }
                        call.transformTo(result);
                    } else if (compensationPreds != null) {
                        RexNode compensationColumnsEquiPred = compensationPreds.getLeft();
                        RexNode otherCompensationPred = RexUtil.composeConjunction(rexBuilder, ImmutableList.of(compensationPreds.getMiddle(), compensationPreds.getRight()), false);
                        // a. Compute final compensation predicate.
                        if (!compensationColumnsEquiPred.isAlwaysTrue() || !otherCompensationPred.isAlwaysTrue()) {
                            // All columns required by compensating predicates must be contained
                            // in the view output (condition 2).
                            List<RexNode> viewExprs = topViewProject == null ? extractReferences(rexBuilder, view) : topViewProject.getChildExps();
                            // since we want to enforce the rest
                            if (!compensationColumnsEquiPred.isAlwaysTrue()) {
                                compensationColumnsEquiPred = rewriteExpression(rexBuilder, mq, view, viewNode, viewExprs, queryToViewTableMapping.inverse(), queryBasedVEC, false, compensationColumnsEquiPred);
                                if (compensationColumnsEquiPred == null) {
                                    // Skip it
                                    continue;
                                }
                            }
                            // For the rest, we use the query equivalence classes
                            if (!otherCompensationPred.isAlwaysTrue()) {
                                otherCompensationPred = rewriteExpression(rexBuilder, mq, view, viewNode, viewExprs, queryToViewTableMapping.inverse(), currQEC, true, otherCompensationPred);
                                if (otherCompensationPred == null) {
                                    // Skip it
                                    continue;
                                }
                            }
                        }
                        final RexNode viewCompensationPred = RexUtil.composeConjunction(rexBuilder, ImmutableList.of(compensationColumnsEquiPred, otherCompensationPred), false);
                        // b. Generate final rewriting if possible.
                        // First, we add the compensation predicate (if any) on top of the view.
                        // Then, we trigger the unifying method. This method will either create a
                        // Project or an Aggregate operator on top of the view. It will also compute
                        // the output expressions for the query.
                        RelBuilder builder = call.builder();
                        RelNode viewWithFilter;
                        if (!viewCompensationPred.isAlwaysTrue()) {
                            RexNode newPred = simplify.simplify(viewCompensationPred);
                            viewWithFilter = builder.push(view).filter(newPred).build();
                            // We add (and push) the filter to the view plan before triggering the rewriting.
                            // This is useful in case some of the columns can be folded to same value after
                            // filter is added.
                            Pair<RelNode, RelNode> pushedNodes = pushFilterToOriginalViewPlan(builder, topViewProject, viewNode, newPred);
                            topViewProject = (Project) pushedNodes.left;
                            viewNode = pushedNodes.right;
                        } else {
                            viewWithFilter = builder.push(view).build();
                        }
                        final RelNode result = rewriteView(builder, rexBuilder, simplify, mq, matchModality, false, viewWithFilter, topProject, node, topViewProject, viewNode, queryToViewTableMapping, currQEC);
                        if (result == null) {
                            // Skip it
                            continue;
                        }
                        call.transformTo(result);
                    }
                // end else
                }
            }
        }
    }
}