Examples with LambdaExpression io.prestosql.sql.tree.LambdaExpression used on opensource projects

Example 1 with LambdaExpression

use of io.prestosql.sql.tree.LambdaExpression in project hetu-core by openlookeng.

the class AstBuilder method visitLambda.

@Override
public Node visitLambda(SqlBaseParser.LambdaContext context) {
    List<LambdaArgumentDeclaration> arguments = visit(context.identifier(), Identifier.class).stream().map(LambdaArgumentDeclaration::new).collect(toList());
    Expression body = (Expression) visit(context.expression());
    return new LambdaExpression(getLocation(context), arguments, body);
}

Example 2 with LambdaExpression

use of io.prestosql.sql.tree.LambdaExpression in project hetu-core by openlookeng.

the class TestDesugarTryExpressionRewriter method testTryExpressionDesugaringRewriter.

@Test
public void testTryExpressionDesugaringRewriter() {
    // 1 + try(2)
    Expression before = new ArithmeticBinaryExpression(ADD, new DecimalLiteral("1"), new TryExpression(new DecimalLiteral("2")));
    // 1 + try_function(() -> 2)
    Expression after = new ArithmeticBinaryExpression(ADD, new DecimalLiteral("1"), new FunctionCallBuilder(tester().getMetadata()).setName(QualifiedName.of(TryFunction.NAME)).addArgument(new FunctionType(ImmutableList.of(), createDecimalType(1)), new LambdaExpression(ImmutableList.of(), new DecimalLiteral("2"))).build());
    assertEquals(DesugarTryExpressionRewriter.rewrite(before, tester().getMetadata(), tester().getTypeAnalyzer(), tester().getSession(), new PlanSymbolAllocator()), after);
}

Example 3 with LambdaExpression

use of io.prestosql.sql.tree.LambdaExpression in project hetu-core by openlookeng.

the class TestEqualityInference method testExpressionsThatMayReturnNullOnNonNullInput.

@Test
public void testExpressionsThatMayReturnNullOnNonNullInput() {
    List<Expression> candidates = ImmutableList.of(// try_cast
    new Cast(nameReference("b"), "BIGINT", true), new FunctionCallBuilder(metadata).setName(QualifiedName.of(TryFunction.NAME)).addArgument(new FunctionType(ImmutableList.of(), VARCHAR), new LambdaExpression(ImmutableList.of(), nameReference("b"))).build(), new NullIfExpression(nameReference("b"), number(1)), new IfExpression(nameReference("b"), number(1), new NullLiteral()), new DereferenceExpression(nameReference("b"), identifier("x")), new InPredicate(nameReference("b"), new InListExpression(ImmutableList.of(new NullLiteral()))), new SearchedCaseExpression(ImmutableList.of(new WhenClause(new IsNotNullPredicate(nameReference("b")), new NullLiteral())), Optional.empty()), new SimpleCaseExpression(nameReference("b"), ImmutableList.of(new WhenClause(number(1), new NullLiteral())), Optional.empty()), new SubscriptExpression(new ArrayConstructor(ImmutableList.of(new NullLiteral())), nameReference("b")));
    for (Expression candidate : candidates) {
        EqualityInference.Builder builder = new EqualityInference.Builder();
        builder.extractInferenceCandidates(equals(nameReference("b"), nameReference("x")));
        builder.extractInferenceCandidates(equals(nameReference("a"), candidate));
        EqualityInference inference = builder.build();
        List<Expression> equalities = inference.generateEqualitiesPartitionedBy(matchesSymbols("b")).getScopeStraddlingEqualities();
        assertEquals(equalities.size(), 1);
        assertTrue(equalities.get(0).equals(equals(nameReference("x"), nameReference("b"))) || equalities.get(0).equals(equals(nameReference("b"), nameReference("x"))));
    }
}

Example 4 with LambdaExpression

use of io.prestosql.sql.tree.LambdaExpression in project hetu-core by openlookeng.

the class QueryPlanner method aggregate.

private PlanBuilder aggregate(PlanBuilder inputSubPlan, QuerySpecification node) {
    PlanBuilder subPlan = inputSubPlan;
    if (!analysis.isAggregation(node)) {
        return subPlan;
    }
    // 1. Pre-project all scalar inputs (arguments and non-trivial group by expressions)
    Set<Expression> groupByExpressions = ImmutableSet.copyOf(analysis.getGroupByExpressions(node));
    ImmutableList.Builder<Expression> arguments = ImmutableList.builder();
    analysis.getAggregates(node).stream().map(FunctionCall::getArguments).flatMap(List::stream).filter(// lambda expression is generated at execution time
    exp -> !(exp instanceof LambdaExpression)).forEach(arguments::add);
    analysis.getAggregates(node).stream().map(FunctionCall::getOrderBy).filter(Optional::isPresent).map(Optional::get).map(OrderBy::getSortItems).flatMap(List::stream).map(SortItem::getSortKey).forEach(arguments::add);
    // filter expressions need to be projected first
    analysis.getAggregates(node).stream().map(FunctionCall::getFilter).filter(Optional::isPresent).map(Optional::get).forEach(arguments::add);
    Iterable<Expression> inputs = Iterables.concat(groupByExpressions, arguments.build());
    subPlan = handleSubqueries(subPlan, node, inputs);
    if (!Iterables.isEmpty(inputs)) {
        // avoid an empty projection if the only aggregation is COUNT (which has no arguments)
        subPlan = project(subPlan, inputs);
    }
    // 2. Aggregate
    // 2.a. Rewrite aggregate arguments
    TranslationMap argumentTranslations = new TranslationMap(subPlan.getRelationPlan(), analysis, lambdaDeclarationToSymbolMap);
    ImmutableList.Builder<Symbol> aggregationArgumentsBuilder = ImmutableList.builder();
    for (Expression argument : arguments.build()) {
        Symbol symbol = subPlan.translate(argument);
        argumentTranslations.put(argument, symbol);
        aggregationArgumentsBuilder.add(symbol);
    }
    List<Symbol> aggregationArguments = aggregationArgumentsBuilder.build();
    // 2.b. Rewrite grouping columns
    TranslationMap groupingTranslations = new TranslationMap(subPlan.getRelationPlan(), analysis, lambdaDeclarationToSymbolMap);
    Map<Symbol, Symbol> groupingSetMappings = new LinkedHashMap<>();
    for (Expression expression : groupByExpressions) {
        Symbol input = subPlan.translate(expression);
        Symbol output = planSymbolAllocator.newSymbol(expression, analysis.getTypeWithCoercions(expression), "gid");
        groupingTranslations.put(expression, output);
        groupingSetMappings.put(output, input);
    }
    // This tracks the grouping sets before complex expressions are considered (see comments below)
    // It's also used to compute the descriptors needed to implement grouping()
    List<Set<FieldId>> columnOnlyGroupingSets = ImmutableList.of(ImmutableSet.of());
    List<List<Symbol>> groupingSets = ImmutableList.of(ImmutableList.of());
    if (node.getGroupBy().isPresent()) {
        // For the purpose of "distinct", we need to canonicalize column references that may have varying
        // syntactic forms (e.g., "t.a" vs "a"). Thus we need to enumerate grouping sets based on the underlying
        // fieldId associated with each column reference expression.
        // The catch is that simple group-by expressions can be arbitrary expressions (this is a departure from the SQL specification).
        // But, they don't affect the number of grouping sets or the behavior of "distinct" . We can compute all the candidate
        // grouping sets in terms of fieldId, dedup as appropriate and then cross-join them with the complex expressions.
        Analysis.GroupingSetAnalysis groupingSetAnalysis = analysis.getGroupingSets(node);
        columnOnlyGroupingSets = enumerateGroupingSets(groupingSetAnalysis);
        if (node.getGroupBy().get().isDistinct()) {
            columnOnlyGroupingSets = columnOnlyGroupingSets.stream().distinct().collect(toImmutableList());
        }
        // add in the complex expressions an turn materialize the grouping sets in terms of plan columns
        ImmutableList.Builder<List<Symbol>> groupingSetBuilder = ImmutableList.builder();
        for (Set<FieldId> groupingSet : columnOnlyGroupingSets) {
            ImmutableList.Builder<Symbol> columns = ImmutableList.builder();
            groupingSetAnalysis.getComplexExpressions().stream().map(groupingTranslations::get).forEach(columns::add);
            groupingSet.stream().map(field -> groupingTranslations.get(new FieldReference(field.getFieldIndex()))).forEach(columns::add);
            groupingSetBuilder.add(columns.build());
        }
        groupingSets = groupingSetBuilder.build();
    }
    // 2.c. Generate GroupIdNode (multiple grouping sets) or ProjectNode (single grouping set)
    Optional<Symbol> groupIdSymbol = Optional.empty();
    if (groupingSets.size() > 1) {
        groupIdSymbol = Optional.of(planSymbolAllocator.newSymbol("groupId", BIGINT));
        GroupIdNode groupId = new GroupIdNode(idAllocator.getNextId(), subPlan.getRoot(), groupingSets, groupingSetMappings, aggregationArguments, groupIdSymbol.get());
        subPlan = new PlanBuilder(groupingTranslations, groupId);
    } else {
        Assignments.Builder assignments = Assignments.builder();
        aggregationArguments.forEach(symbol -> assignments.put(symbol, castToRowExpression(toSymbolReference(symbol))));
        groupingSetMappings.forEach((key, value) -> assignments.put(key, castToRowExpression(toSymbolReference(value))));
        ProjectNode project = new ProjectNode(idAllocator.getNextId(), subPlan.getRoot(), assignments.build());
        subPlan = new PlanBuilder(groupingTranslations, project);
    }
    TranslationMap aggregationTranslations = new TranslationMap(subPlan.getRelationPlan(), analysis, lambdaDeclarationToSymbolMap);
    aggregationTranslations.copyMappingsFrom(groupingTranslations);
    // 2.d. Rewrite aggregates
    ImmutableMap.Builder<Symbol, Aggregation> aggregationsBuilder = ImmutableMap.builder();
    boolean needPostProjectionCoercion = false;
    for (FunctionCall aggregate : analysis.getAggregates(node)) {
        Expression rewritten = argumentTranslations.rewrite(aggregate);
        Symbol newSymbol = planSymbolAllocator.newSymbol(rewritten, analysis.getType(aggregate));
        // Therefore we can end up with this implicit cast, and have to move it into a post-projection
        if (rewritten instanceof Cast) {
            rewritten = ((Cast) rewritten).getExpression();
            needPostProjectionCoercion = true;
        }
        aggregationTranslations.put(aggregate, newSymbol);
        FunctionCall functionCall = (FunctionCall) rewritten;
        aggregationsBuilder.put(newSymbol, new Aggregation(call(aggregate.getName().getSuffix(), analysis.getFunctionHandle(aggregate), analysis.getType(aggregate), functionCall.getArguments().stream().map(OriginalExpressionUtils::castToRowExpression).collect(toImmutableList())), functionCall.getArguments().stream().map(OriginalExpressionUtils::castToRowExpression).collect(toImmutableList()), functionCall.isDistinct(), functionCall.getFilter().map(SymbolUtils::from), functionCall.getOrderBy().map(OrderingSchemeUtils::fromOrderBy), Optional.empty()));
    }
    Map<Symbol, Aggregation> aggregations = aggregationsBuilder.build();
    ImmutableSet.Builder<Integer> globalGroupingSets = ImmutableSet.builder();
    for (int i = 0; i < groupingSets.size(); i++) {
        if (groupingSets.get(i).isEmpty()) {
            globalGroupingSets.add(i);
        }
    }
    ImmutableList.Builder<Symbol> groupingKeys = ImmutableList.builder();
    groupingSets.stream().flatMap(List::stream).distinct().forEach(groupingKeys::add);
    groupIdSymbol.ifPresent(groupingKeys::add);
    AggregationNode aggregationNode = new AggregationNode(idAllocator.getNextId(), subPlan.getRoot(), aggregations, groupingSets(groupingKeys.build(), groupingSets.size(), globalGroupingSets.build()), ImmutableList.of(), AggregationNode.Step.SINGLE, Optional.empty(), groupIdSymbol, AggregationNode.AggregationType.HASH, Optional.empty());
    subPlan = new PlanBuilder(aggregationTranslations, aggregationNode);
    // TODO: this is a hack, we should change type coercions to coerce the inputs to functions/operators instead of coercing the output
    if (needPostProjectionCoercion) {
        ImmutableList.Builder<Expression> alreadyCoerced = ImmutableList.builder();
        alreadyCoerced.addAll(groupByExpressions);
        groupIdSymbol.map(SymbolUtils::toSymbolReference).ifPresent(alreadyCoerced::add);
        subPlan = explicitCoercionFields(subPlan, alreadyCoerced.build(), analysis.getAggregates(node));
    }
    // 4. Project and re-write all grouping functions
    return handleGroupingOperations(subPlan, node, groupIdSymbol, columnOnlyGroupingSets);
}

Example 5 with LambdaExpression

use of io.prestosql.sql.tree.LambdaExpression in project hetu-core by openlookeng.

the class ImpalaAstBuilder method visitLambda.

@Override
public Node visitLambda(ImpalaSqlParser.LambdaContext context) {
    List<LambdaArgumentDeclaration> arguments = visit(context.identifier(), Identifier.class).stream().map(LambdaArgumentDeclaration::new).collect(toList());
    Expression body = (Expression) visit(context.expression());
    return new LambdaExpression(getLocation(context), arguments, body);
}