final SqlValidator validator =
new OptiqSqlValidator(opTab, catalogReader, typeFactory);
validator.setIdentifierExpansion(true);
final List<Prepare.Materialization> materializations =
config.materializationsEnabled()
? MaterializationService.instance().query(rootSchema)
: ImmutableList.<Prepare.Materialization>of();
for (Prepare.Materialization materialization : materializations) {
populateMaterializations(context, planner, materialization);
}