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

Example 1 with IsNotNullPredicate

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

the class DecorrelateInnerUnnestWithGlobalAggregation method apply.

@Override
public Result apply(CorrelatedJoinNode correlatedJoinNode, Captures captures, Context context) {
    // find global aggregation in subquery
    List<PlanNode> globalAggregations = PlanNodeSearcher.searchFrom(correlatedJoinNode.getSubquery(), context.getLookup()).where(DecorrelateInnerUnnestWithGlobalAggregation::isGlobalAggregation).recurseOnlyWhen(node -> node instanceof ProjectNode || isGlobalAggregation(node)).findAll();
    if (globalAggregations.isEmpty()) {
        return Result.empty();
    }
    // if there are multiple global aggregations, the one that is closest to the source is the "reducing" aggregation, because it reduces multiple input rows to single output row
    AggregationNode reducingAggregation = (AggregationNode) globalAggregations.get(globalAggregations.size() - 1);
    // find unnest in subquery
    Optional<UnnestNode> subqueryUnnest = PlanNodeSearcher.searchFrom(reducingAggregation.getSource(), context.getLookup()).where(node -> isSupportedUnnest(node, correlatedJoinNode.getCorrelation(), context.getLookup())).recurseOnlyWhen(node -> node instanceof ProjectNode || isGroupedAggregation(node)).findFirst();
    if (subqueryUnnest.isEmpty()) {
        return Result.empty();
    }
    UnnestNode unnestNode = subqueryUnnest.get();
    // assign unique id to input rows to restore semantics of aggregations after rewrite
    PlanNode input = new AssignUniqueId(context.getIdAllocator().getNextId(), correlatedJoinNode.getInput(), context.getSymbolAllocator().newSymbol("unique", BIGINT));
    // 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());
    }
    // rewrite correlated join to UnnestNode
    Symbol ordinalitySymbol = unnestNode.getOrdinalitySymbol().orElseGet(() -> context.getSymbolAllocator().newSymbol("ordinality", BIGINT));
    UnnestNode rewrittenUnnest = new UnnestNode(context.getIdAllocator().getNextId(), input, input.getOutputSymbols(), unnestNode.getMappings(), Optional.of(ordinalitySymbol), LEFT, Optional.empty());
    // append mask symbol based on ordinality to distinguish between the unnested rows and synthetic null rows
    Symbol mask = context.getSymbolAllocator().newSymbol("mask", BOOLEAN);
    ProjectNode sourceWithMask = new ProjectNode(context.getIdAllocator().getNextId(), rewrittenUnnest, Assignments.builder().putIdentities(rewrittenUnnest.getOutputSymbols()).put(mask, new IsNotNullPredicate(ordinalitySymbol.toSymbolReference())).build());
    // restore all projections, grouped aggregations and global aggregations from the subquery
    PlanNode result = rewriteNodeSequence(context.getLookup().resolve(correlatedJoinNode.getSubquery()), input.getOutputSymbols(), mask, sourceWithMask, reducingAggregation.getId(), unnestNode.getId(), context.getSymbolAllocator(), context.getIdAllocator(), context.getLookup());
    // restrict outputs
    return Result.ofPlanNode(restrictOutputs(context.getIdAllocator(), result, ImmutableSet.copyOf(correlatedJoinNode.getOutputSymbols())).orElse(result));
}

Example 2 with IsNotNullPredicate

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

the class TestEqualityInference method testExpressionsThatMayReturnNullOnNonNullInput.

@Test
public void testExpressionsThatMayReturnNullOnNonNullInput() {
    List<Expression> candidates = ImmutableList.of(// try_cast
    new Cast(nameReference("b"), toSqlType(BIGINT), true), functionResolution.functionCallBuilder(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 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 inference = EqualityInference.newInstance(metadata, equals(nameReference("b"), nameReference("x")), equals(nameReference("a"), candidate));
        List<Expression> equalities = inference.generateEqualitiesPartitionedBy(symbols("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"))));
    }
}