Examples with ExternalSet org.openrdf.query.algebra.evaluation.impl.ExternalSet used on opensource projects

Example 1 with ExternalSet

use of org.openrdf.query.algebra.evaluation.impl.ExternalSet in project incubator-rya by apache.

the class AccumuloSelectivityEvalDAO method getSpJoinSelect.

// TODO currently computes average selectivity of sp1 with each node in TupleExpr te (is this best?)
private double getSpJoinSelect(RdfCloudTripleStoreConfiguration conf, TupleExpr te, StatementPattern sp1) throws TableNotFoundException {
    if (te instanceof StatementPattern) {
        return getJoinSelect(conf, (StatementPattern) te, sp1);
    } else {
        SpExternalCollector spe = new SpExternalCollector();
        te.visit(spe);
        List<QueryModelNode> espList = spe.getSpExtTup();
        if (espList.size() == 0) {
            Set<String> tupBn = te.getAssuredBindingNames();
            Set<String> eBn = sp1.getAssuredBindingNames();
            Set<String> intersect = Sets.intersection(tupBn, eBn);
            return Math.pow(1.0 / 10000.0, intersect.size());
        }
        double min = Double.MAX_VALUE;
        double select = Double.MAX_VALUE;
        for (QueryModelNode node : espList) {
            if (node instanceof StatementPattern)
                select = getJoinSelect(conf, sp1, (StatementPattern) node);
            else if (node instanceof ExternalSet) {
                select = getExtJoinSelect(sp1, (ExternalSet) node);
            }
            if (min > select) {
                min = select;
            }
        }
        // System.out.println("Max is " + max);
        return min;
    }
}