Examples with UnboundMetadata org.apache.calcite.rel.metadata.UnboundMetadata used on opensource projects

Example 1 with UnboundMetadata

use of org.apache.calcite.rel.metadata.UnboundMetadata in project calcite by apache.

the class HepRelMetadataProvider method apply.

public <M extends Metadata> UnboundMetadata<M> apply(Class<? extends RelNode> relClass, final Class<? extends M> metadataClass) {
    return new UnboundMetadata<M>() {

        public M bind(RelNode rel, RelMetadataQuery mq) {
            if (!(rel instanceof HepRelVertex)) {
                return null;
            }
            HepRelVertex vertex = (HepRelVertex) rel;
            final RelNode rel2 = vertex.getCurrentRel();
            UnboundMetadata<M> function = rel.getCluster().getMetadataProvider().apply(rel2.getClass(), metadataClass);
            return function.bind(rel2, mq);
        }
    };
}

Example 2 with UnboundMetadata

use of org.apache.calcite.rel.metadata.UnboundMetadata in project calcite by apache.

the class VolcanoRelMetadataProvider method apply.

public <M extends Metadata> UnboundMetadata<M> apply(Class<? extends RelNode> relClass, final Class<? extends M> metadataClass) {
    if (relClass != RelSubset.class) {
        // let someone else further down the chain sort it out
        return null;
    }
    return new UnboundMetadata<M>() {

        public M bind(RelNode rel, RelMetadataQuery mq) {
            final RelSubset subset = (RelSubset) rel;
            final RelMetadataProvider provider = rel.getCluster().getMetadataProvider();
            // this query, treat it as the most reliable.
            if (subset.best != null) {
                final UnboundMetadata<M> function = provider.apply(subset.best.getClass(), metadataClass);
                if (function != null) {
                    final M metadata = function.bind(subset.best, mq);
                    if (metadata != null) {
                        return metadata;
                    }
                }
            }
            // granularity).
            if (subset.set.inMetadataQuery) {
                return null;
            }
            subset.set.inMetadataQuery = true;
            try {
                for (RelNode relCandidate : subset.set.rels) {
                    final UnboundMetadata<M> function = provider.apply(relCandidate.getClass(), metadataClass);
                    if (function != null) {
                        final M result = function.bind(relCandidate, mq);
                        if (result != null) {
                            return result;
                        }
                    }
                }
            } finally {
                subset.set.inMetadataQuery = false;
            }
            // Give up.
            return null;
        }
    };
}