if (!CapabilitiesUtil.useAnsiJoin(RuleRaiseAccess.getModelIDFromAccess(accessRoot, metadata), metadata, capFinder)) {
simplifyFromClause(query);
}
if (columns.isEmpty()) {
if (CapabilitiesUtil.supports(Capability.QUERY_SELECT_EXPRESSION, RuleRaiseAccess.getModelIDFromAccess(accessRoot, metadata), metadata, capFinder)) {
select.addSymbol(new ExpressionSymbol("dummy", new Constant(1))); //$NON-NLS-1$
} else {
//TODO: need to ensure the type is consistent
//- should be rare as the source would typically support select expression if it supports union
select.addSymbol(selectOutputElement(query.getFrom().getGroups(), metadata));
}