SetMultimap<Symbol, Integer> indexLookupToProbeInput = mapIndexSourceLookupSymbolToProbeKeyInput(node, probeKeyLayout);
LocalExecutionPlanContext indexContext = context.createIndexSourceSubContext(new IndexSourceContext(indexLookupToProbeInput));
PhysicalOperation indexSource = node.getIndexSource().accept(this, indexContext);
List<Integer> indexChannels = getChannelsForSymbols(indexSymbols, indexSource.getLayout());
PagesIndexBuilderOperatorFactory pagesIndexOutput = new PagesIndexBuilderOperatorFactory(
indexContext.getNextOperatorId(),
indexSource.getTypes()
);
DriverFactory indexBuildDriverFactory = new DriverFactory(