Examples with UnnestNode io.trino.sql.planner.plan.UnnestNode used on opensource projects

Example 11 with UnnestNode

use of io.trino.sql.planner.plan.UnnestNode in project trino by trinodb.

the class UnnestedSymbolMatcher method getAssignedSymbol.

@Override
public Optional<Symbol> getAssignedSymbol(PlanNode node, Session session, Metadata metadata, SymbolAliases symbolAliases) {
    if (!(node instanceof UnnestNode)) {
        return Optional.empty();
    }
    UnnestNode unnestNode = (UnnestNode) node;
    Symbol unnestSymbol = Symbol.from(symbolAliases.get(symbol));
    List<Mapping> matches = unnestNode.getMappings().stream().filter(mapping -> mapping.getInput().equals(unnestSymbol)).collect(toImmutableList());
    checkState(matches.size() < 2, "alias matching not supported for repeated unnest symbols");
    if (matches.size() == 0) {
        return Optional.empty();
    }
    Mapping mapping = getOnlyElement(matches);
    if (index >= mapping.getOutputs().size()) {
        return Optional.empty();
    }
    return Optional.of(mapping.getOutputs().get(index));
}

Example 12 with UnnestNode

use of io.trino.sql.planner.plan.UnnestNode in project trino by trinodb.

the class PushDownDereferenceThroughUnnest method apply.

@Override
public Result apply(ProjectNode projectNode, Captures captures, Context context) {
    UnnestNode unnestNode = captures.get(CHILD);
    // Extract dereferences from project node's assignments and unnest node's filter
    ImmutableList.Builder<Expression> expressionsBuilder = ImmutableList.builder();
    expressionsBuilder.addAll(projectNode.getAssignments().getExpressions());
    unnestNode.getFilter().ifPresent(expressionsBuilder::add);
    // Extract dereferences for pushdown
    Set<SubscriptExpression> dereferences = extractRowSubscripts(expressionsBuilder.build(), false, context.getSession(), typeAnalyzer, context.getSymbolAllocator().getTypes());
    // Only retain dereferences on replicate symbols
    dereferences = dereferences.stream().filter(expression -> unnestNode.getReplicateSymbols().contains(getBase(expression))).collect(toImmutableSet());
    if (dereferences.isEmpty()) {
        return Result.empty();
    }
    // Create new symbols for dereference expressions
    Assignments dereferenceAssignments = Assignments.of(dereferences, context.getSession(), context.getSymbolAllocator(), typeAnalyzer);
    // Rewrite project node assignments using new symbols for dereference expressions
    Map<Expression, SymbolReference> mappings = HashBiMap.create(dereferenceAssignments.getMap()).inverse().entrySet().stream().collect(toImmutableMap(Map.Entry::getKey, entry -> entry.getValue().toSymbolReference()));
    Assignments newAssignments = projectNode.getAssignments().rewrite(expression -> replaceExpression(expression, mappings));
    // Create a new ProjectNode (above the original source) adding dereference projections on replicated symbols
    ProjectNode source = new ProjectNode(context.getIdAllocator().getNextId(), unnestNode.getSource(), Assignments.builder().putIdentities(unnestNode.getSource().getOutputSymbols()).putAll(dereferenceAssignments).build());
    // Create projectNode with the new unnest node and assignments with replaced dereferences
    return Result.ofPlanNode(new ProjectNode(context.getIdAllocator().getNextId(), new UnnestNode(context.getIdAllocator().getNextId(), source, ImmutableList.<Symbol>builder().addAll(unnestNode.getReplicateSymbols()).addAll(dereferenceAssignments.getSymbols()).build(), unnestNode.getMappings(), unnestNode.getOrdinalitySymbol(), unnestNode.getJoinType(), unnestNode.getFilter().map(filter -> replaceExpression(filter, mappings))), newAssignments));
}