@Override
public boolean indexAccessible(final IndexInfo ii) throws QueryException {
final int es = exprs.length;
final boolean[] ng = new boolean[es];
int costs = 0;
for (final FTExpr expr : exprs) {
if (!expr.indexAccessible(ii)) return false;
// use worst costs for estimation, as all index results may need to be scanned
if (costs < ii.costs) costs = ii.costs;
}
ii.costs = costs;
negated = ng;
return true;
}
