if (groupBy != null) {
ASTBuilder b = ASTBuilder.construct(HiveParser.TOK_GROUPBY, "TOK_GROUPBY");
for (int i : BitSets.toIter(groupBy.getGroupSet())) {
RexInputRef iRef = new RexInputRef(i, groupBy.getCluster().getTypeFactory()
.createSqlType(SqlTypeName.ANY));
b.add(iRef.accept(new RexVisitor(schema)));
}
if (!groupBy.getGroupSet().isEmpty())
hiveAST.groupBy = b.node();
schema = new Schema(schema, groupBy);