@Override
protected RelationPlan visitTable(Table node, Void context) {
Query namedQuery = analysis.getNamedQuery(node);
if (namedQuery != null) {
RelationPlan subPlan = process(namedQuery, null);
return new RelationPlan(
subPlan.getRoot(),
analysis.getOutputDescriptor(node),
subPlan.getOutputSymbols(),
subPlan.getSampleWeight());
}
TupleDescriptor descriptor = analysis.getOutputDescriptor(node);
TableHandle handle = analysis.getTableHandle(node);
ImmutableList.Builder<Symbol> outputSymbolsBuilder = ImmutableList.builder();
ImmutableMap.Builder<Symbol, ColumnHandle> columns = ImmutableMap.builder();
for (Field field : descriptor.getAllFields()) {
Symbol symbol = symbolAllocator.newSymbol(field.getName().get(), field.getType());
outputSymbolsBuilder.add(symbol);
columns.put(symbol, analysis.getColumn(field));
}
List<Symbol> planOutputSymbols = outputSymbolsBuilder.build();
Optional<ColumnHandle> sampleWeightColumn =
metadata.getSampleWeightColumnHandle(session, handle);
Symbol sampleWeightSymbol = null;
if (sampleWeightColumn.isPresent()) {
sampleWeightSymbol = symbolAllocator.newSymbol("$sampleWeight", BIGINT);
outputSymbolsBuilder.add(sampleWeightSymbol);
columns.put(sampleWeightSymbol, sampleWeightColumn.get());
}
List<Symbol> nodeOutputSymbols = outputSymbolsBuilder.build();
PlanNode root =
new TableScanNode(
idAllocator.getNextId(),
handle,
nodeOutputSymbols,
columns.build(),
Optional.empty(),
TupleDomain.all(),
null);
return new RelationPlan(
root, descriptor, planOutputSymbols, Optional.ofNullable(sampleWeightSymbol));
}
private RelationPlan processAndCoerceIfNecessary(Relation node, Void context) {
Type[] coerceToTypes = analysis.getRelationCoercion(node);
RelationPlan plan = node.accept(this, context);
if (coerceToTypes == null) {
return plan;
}
List<Symbol> oldSymbols = plan.getOutputSymbols();
TupleDescriptor oldDescriptor = plan.getDescriptor().withOnlyVisibleFields();
verify(coerceToTypes.length == oldSymbols.size());
ImmutableList.Builder<Symbol> newSymbols = new ImmutableList.Builder<>();
Field[] newFields = new Field[coerceToTypes.length];
ImmutableMap.Builder<Symbol, Expression> assignments = new ImmutableMap.Builder<>();
for (int i = 0; i < coerceToTypes.length; i++) {
Symbol inputSymbol = oldSymbols.get(i);
Type inputType = symbolAllocator.getTypes().get(inputSymbol);
Type outputType = coerceToTypes[i];
if (outputType != inputType) {
Cast cast =
new Cast(
new QualifiedNameReference(inputSymbol.toQualifiedName()),
outputType.getTypeSignature().toString());
Symbol outputSymbol = symbolAllocator.newSymbol(cast, outputType);
assignments.put(outputSymbol, cast);
newSymbols.add(outputSymbol);
} else {
assignments.put(inputSymbol, new QualifiedNameReference(inputSymbol.toQualifiedName()));
newSymbols.add(inputSymbol);
}
Field oldField = oldDescriptor.getFieldByIndex(i);
newFields[i] =
new Field(
oldField.getRelationAlias(),
oldField.getName(),
coerceToTypes[i],
oldField.isHidden());
}
ProjectNode projectNode =
new ProjectNode(idAllocator.getNextId(), plan.getRoot(), assignments.build());
return new RelationPlan(
projectNode, new TupleDescriptor(newFields), newSymbols.build(), plan.getSampleWeight());
}