Examples with NullLiteral io.trino.sql.tree.NullLiteral used on opensource projects

Example 16 with NullLiteral

use of io.trino.sql.tree.NullLiteral in project trino by trinodb.

the class DecorrelateUnnest method apply.

@Override
public Result apply(CorrelatedJoinNode correlatedJoinNode, Captures captures, Context context) {
    // determine shape of the subquery
    PlanNode searchRoot = correlatedJoinNode.getSubquery();
    // 1. find EnforceSingleRowNode in the subquery
    Optional<EnforceSingleRowNode> enforceSingleRow = PlanNodeSearcher.searchFrom(searchRoot, context.getLookup()).where(EnforceSingleRowNode.class::isInstance).recurseOnlyWhen(planNode -> false).findFirst();
    if (enforceSingleRow.isPresent()) {
        searchRoot = enforceSingleRow.get().getSource();
    }
    // 2. find correlated UnnestNode in the subquery
    Optional<UnnestNode> subqueryUnnest = PlanNodeSearcher.searchFrom(searchRoot, context.getLookup()).where(node -> isSupportedUnnest(node, correlatedJoinNode.getCorrelation(), context.getLookup())).recurseOnlyWhen(node -> node instanceof ProjectNode || (node instanceof LimitNode && ((LimitNode) node).getCount() > 0) || (node instanceof TopNNode && ((TopNNode) node).getCount() > 0)).findFirst();
    if (subqueryUnnest.isEmpty()) {
        return Result.empty();
    }
    UnnestNode unnestNode = subqueryUnnest.get();
    // assign unique id to input rows
    Symbol uniqueSymbol = context.getSymbolAllocator().newSymbol("unique", BIGINT);
    PlanNode input = new AssignUniqueId(context.getIdAllocator().getNextId(), correlatedJoinNode.getInput(), uniqueSymbol);
    // pre-project unnest symbols if they were pre-projected in subquery
    // The correlated UnnestNode either unnests correlation symbols directly, or unnests symbols produced by a projection that uses only correlation symbols.
    // Here, any underlying projection that was a source of the correlated UnnestNode, is appended as a source of the rewritten UnnestNode.
    // If the projection is not necessary for UnnestNode (i.e. it does not produce any unnest symbols), it should be pruned afterwards.
    PlanNode unnestSource = context.getLookup().resolve(unnestNode.getSource());
    if (unnestSource instanceof ProjectNode) {
        ProjectNode sourceProjection = (ProjectNode) unnestSource;
        input = new ProjectNode(sourceProjection.getId(), input, Assignments.builder().putIdentities(input.getOutputSymbols()).putAll(sourceProjection.getAssignments()).build());
    }
    // determine join type for rewritten UnnestNode
    Type unnestJoinType = LEFT;
    if (enforceSingleRow.isEmpty() && correlatedJoinNode.getType() == CorrelatedJoinNode.Type.INNER && unnestNode.getJoinType() == INNER) {
        unnestJoinType = INNER;
    }
    // make sure that the rewritten node is with ordinality, which might be necessary to restore inner unnest semantics after rewrite.
    Symbol ordinalitySymbol = unnestNode.getOrdinalitySymbol().orElseGet(() -> context.getSymbolAllocator().newSymbol("ordinality", BIGINT));
    // rewrite correlated join to UnnestNode.
    UnnestNode rewrittenUnnest = new UnnestNode(context.getIdAllocator().getNextId(), input, input.getOutputSymbols(), unnestNode.getMappings(), Optional.of(ordinalitySymbol), unnestJoinType, Optional.empty());
    // restore all nodes from the subquery
    PlanNode rewrittenPlan = Rewriter.rewriteNodeSequence(correlatedJoinNode.getSubquery(), input.getOutputSymbols(), ordinalitySymbol, uniqueSymbol, rewrittenUnnest, context.getSession(), metadata, context.getLookup(), context.getIdAllocator(), context.getSymbolAllocator());
    // between unnested rows and synthetic rows added by left unnest.
    if (unnestNode.getJoinType() == INNER && rewrittenUnnest.getJoinType() == LEFT) {
        Assignments.Builder assignments = Assignments.builder().putIdentities(correlatedJoinNode.getInput().getOutputSymbols());
        for (Symbol subquerySymbol : correlatedJoinNode.getSubquery().getOutputSymbols()) {
            assignments.put(subquerySymbol, new IfExpression(new IsNullPredicate(ordinalitySymbol.toSymbolReference()), new Cast(new NullLiteral(), toSqlType(context.getSymbolAllocator().getTypes().get(subquerySymbol))), subquerySymbol.toSymbolReference()));
        }
        rewrittenPlan = new ProjectNode(context.getIdAllocator().getNextId(), rewrittenPlan, assignments.build());
    }
    // restrict outputs
    return Result.ofPlanNode(restrictOutputs(context.getIdAllocator(), rewrittenPlan, ImmutableSet.copyOf(correlatedJoinNode.getOutputSymbols())).orElse(rewrittenPlan));
}

Example 17 with NullLiteral

use of io.trino.sql.tree.NullLiteral in project trino by trinodb.

the class TestReplaceRedundantJoinWithProject method testReplaceFULLJoin.

@Test
public void testReplaceFULLJoin() {
    tester().assertThat(new ReplaceRedundantJoinWithProject()).on(p -> p.join(FULL, p.values(10, p.symbol("a")), p.values(0, p.symbol("b")))).matches(project(ImmutableMap.of("a", expression("a"), "b", expression("CAST(null AS bigint)")), values(ImmutableList.of("a"), nCopies(10, ImmutableList.of(new NullLiteral())))));
    tester().assertThat(new ReplaceRedundantJoinWithProject()).on(p -> p.join(FULL, p.values(0, p.symbol("a")), p.values(10, p.symbol("b")))).matches(project(ImmutableMap.of("a", expression("CAST(null AS bigint)"), "b", expression("b")), values(ImmutableList.of("b"), nCopies(10, ImmutableList.of(new NullLiteral())))));
}

Example 18 with NullLiteral

use of io.trino.sql.tree.NullLiteral in project trino by trinodb.

the class TestReplaceRedundantJoinWithSource method testReplaceInnerJoinWithFilter.

@Test
public void testReplaceInnerJoinWithFilter() {
    tester().assertThat(new ReplaceRedundantJoinWithSource()).on(p -> p.join(INNER, p.values(10, p.symbol("a")), p.values(1), expression("a > 0"))).matches(filter("a > 0", values(ImmutableList.of("a"), nCopies(10, ImmutableList.of(new NullLiteral())))));
    tester().assertThat(new ReplaceRedundantJoinWithSource()).on(p -> p.join(INNER, p.values(1), p.values(10, p.symbol("b")), expression("b > 0"))).matches(filter("b > 0", values(ImmutableList.of("b"), nCopies(10, ImmutableList.of(new NullLiteral())))));
}

Example 19 with NullLiteral

use of io.trino.sql.tree.NullLiteral in project trino by trinodb.

the class PushAggregationThroughOuterJoin method createAggregationOverNull.

private MappedAggregationInfo createAggregationOverNull(AggregationNode referenceAggregation, SymbolAllocator symbolAllocator, PlanNodeIdAllocator idAllocator) {
    // Create a values node that consists of a single row of nulls.
    // Map the output symbols from the referenceAggregation's source
    // to symbol references for the new values node.
    ImmutableList.Builder<Symbol> nullSymbols = ImmutableList.builder();
    ImmutableList.Builder<Expression> nullLiterals = ImmutableList.builder();
    ImmutableMap.Builder<Symbol, Symbol> sourcesSymbolMappingBuilder = ImmutableMap.builder();
    for (Symbol sourceSymbol : referenceAggregation.getSource().getOutputSymbols()) {
        Type type = symbolAllocator.getTypes().get(sourceSymbol);
        nullLiterals.add(new Cast(new NullLiteral(), toSqlType(type)));
        Symbol nullSymbol = symbolAllocator.newSymbol("null", type);
        nullSymbols.add(nullSymbol);
        sourcesSymbolMappingBuilder.put(sourceSymbol, nullSymbol);
    }
    ValuesNode nullRow = new ValuesNode(idAllocator.getNextId(), nullSymbols.build(), ImmutableList.of(new Row(nullLiterals.build())));
    // For each aggregation function in the reference node, create a corresponding aggregation function
    // that points to the nullRow. Map the symbols from the aggregations in referenceAggregation to the
    // symbols in these new aggregations.
    ImmutableMap.Builder<Symbol, Symbol> aggregationsSymbolMappingBuilder = ImmutableMap.builder();
    ImmutableMap.Builder<Symbol, AggregationNode.Aggregation> aggregationsOverNullBuilder = ImmutableMap.builder();
    SymbolMapper mapper = symbolMapper(sourcesSymbolMappingBuilder.buildOrThrow());
    for (Map.Entry<Symbol, AggregationNode.Aggregation> entry : referenceAggregation.getAggregations().entrySet()) {
        Symbol aggregationSymbol = entry.getKey();
        Aggregation overNullAggregation = mapper.map(entry.getValue());
        Symbol overNullSymbol = symbolAllocator.newSymbol(overNullAggregation.getResolvedFunction().getSignature().getName(), symbolAllocator.getTypes().get(aggregationSymbol));
        aggregationsOverNullBuilder.put(overNullSymbol, overNullAggregation);
        aggregationsSymbolMappingBuilder.put(aggregationSymbol, overNullSymbol);
    }
    Map<Symbol, Symbol> aggregationsSymbolMapping = aggregationsSymbolMappingBuilder.buildOrThrow();
    // create an aggregation node whose source is the null row.
    AggregationNode aggregationOverNullRow = new AggregationNode(idAllocator.getNextId(), nullRow, aggregationsOverNullBuilder.buildOrThrow(), globalAggregation(), ImmutableList.of(), AggregationNode.Step.SINGLE, Optional.empty(), Optional.empty());
    return new MappedAggregationInfo(aggregationOverNullRow, aggregationsSymbolMapping);
}

Example 20 with NullLiteral

use of io.trino.sql.tree.NullLiteral in project trino by trinodb.

the class ReplaceRedundantJoinWithProject method appendNulls.

private static ProjectNode appendNulls(PlanNode source, List<Symbol> sourceOutputs, List<Symbol> nullSymbols, PlanNodeIdAllocator idAllocator, SymbolAllocator symbolAllocator) {
    Assignments.Builder assignments = Assignments.builder().putIdentities(sourceOutputs);
    nullSymbols.stream().forEach(symbol -> assignments.put(symbol, new Cast(new NullLiteral(), toSqlType(symbolAllocator.getTypes().get(symbol)))));
    return new ProjectNode(idAllocator.getNextId(), source, assignments.build());
}