Examples with CorrelationReferenceFinder org.apache.calcite.sql2rel.CorrelationReferenceFinder used on opensource projects

Example 1 with CorrelationReferenceFinder

use of org.apache.calcite.sql2rel.CorrelationReferenceFinder in project hive by apache.

the class RelFieldTrimmer method trimChild.

/**
 * Trims the fields of an input relational expression.
 *
 * @param rel        Relational expression
 * @param input      Input relational expression, whose fields to trim
 * @param fieldsUsed Bitmap of fields needed by the consumer
 * @return New relational expression and its field mapping
 */
protected TrimResult trimChild(RelNode rel, RelNode input, final ImmutableBitSet fieldsUsed, Set<RelDataTypeField> extraFields) {
    final ImmutableBitSet.Builder fieldsUsedBuilder = fieldsUsed.rebuild();
    // Fields that define the collation cannot be discarded.
    final RelMetadataQuery mq = rel.getCluster().getMetadataQuery();
    final ImmutableList<RelCollation> collations = mq.collations(input);
    if (collations != null) {
        for (RelCollation collation : collations) {
            for (RelFieldCollation fieldCollation : collation.getFieldCollations()) {
                fieldsUsedBuilder.set(fieldCollation.getFieldIndex());
            }
        }
    }
    // fields.
    for (final CorrelationId correlation : rel.getVariablesSet()) {
        rel.accept(new CorrelationReferenceFinder() {

            protected RexNode handle(RexFieldAccess fieldAccess) {
                final RexCorrelVariable v = (RexCorrelVariable) fieldAccess.getReferenceExpr();
                if (v.id.equals(correlation)) {
                    fieldsUsedBuilder.set(fieldAccess.getField().getIndex());
                }
                return fieldAccess;
            }
        });
    }
    return dispatchTrimFields(input, fieldsUsedBuilder.build(), extraFields);
}

Example 2 with CorrelationReferenceFinder

use of org.apache.calcite.sql2rel.CorrelationReferenceFinder in project hive by apache.

the class RelFieldTrimmer method result.

protected TrimResult result(RelNode r, final Mapping mapping) {
    final RelBuilder relBuilder = REL_BUILDER.get();
    final RexBuilder rexBuilder = relBuilder.getRexBuilder();
    for (final CorrelationId correlation : r.getVariablesSet()) {
        r = r.accept(new CorrelationReferenceFinder() {

            protected RexNode handle(RexFieldAccess fieldAccess) {
                final RexCorrelVariable v = (RexCorrelVariable) fieldAccess.getReferenceExpr();
                if (v.id.equals(correlation) && v.getType().getFieldCount() == mapping.getSourceCount()) {
                    final int old = fieldAccess.getField().getIndex();
                    final int new_ = mapping.getTarget(old);
                    final RelDataTypeFactory.Builder typeBuilder = relBuilder.getTypeFactory().builder();
                    for (int target : Util.range(mapping.getTargetCount())) {
                        typeBuilder.add(v.getType().getFieldList().get(mapping.getSource(target)));
                    }
                    final RexNode newV = rexBuilder.makeCorrel(typeBuilder.build(), v.id);
                    if (old != new_) {
                        return rexBuilder.makeFieldAccess(newV, new_);
                    }
                }
                return fieldAccess;
            }
        });
    }
    return new TrimResult(r, mapping);
}