Examples with MultiJoin org.apache.calcite.rel.rules.MultiJoin used on opensource projects

Example 1 with MultiJoin

use of org.apache.calcite.rel.rules.MultiJoin in project calcite by apache.

the class RelOptUtil method projectMultiJoin.

/**
 * Creates a new {@link org.apache.calcite.rel.rules.MultiJoin} to reflect
 * projection references from a
 * {@link org.apache.calcite.rel.logical.LogicalProject} that is on top of the
 * {@link org.apache.calcite.rel.rules.MultiJoin}.
 *
 * @param multiJoin the original MultiJoin
 * @param project   the LogicalProject on top of the MultiJoin
 * @return the new MultiJoin
 */
public static MultiJoin projectMultiJoin(MultiJoin multiJoin, LogicalProject project) {
    // Locate all input references in the projection expressions as well
    // the post-join filter.  Since the filter effectively sits in
    // between the LogicalProject and the MultiJoin, the projection needs
    // to include those filter references.
    ImmutableBitSet inputRefs = InputFinder.bits(project.getProjects(), multiJoin.getPostJoinFilter());
    // create new copies of the bitmaps
    List<RelNode> multiJoinInputs = multiJoin.getInputs();
    List<BitSet> newProjFields = Lists.newArrayList();
    for (RelNode multiJoinInput : multiJoinInputs) {
        newProjFields.add(new BitSet(multiJoinInput.getRowType().getFieldCount()));
    }
    // set the bits found in the expressions
    int currInput = -1;
    int startField = 0;
    int nFields = 0;
    for (int bit : inputRefs) {
        while (bit >= (startField + nFields)) {
            startField += nFields;
            currInput++;
            assert currInput < multiJoinInputs.size();
            nFields = multiJoinInputs.get(currInput).getRowType().getFieldCount();
        }
        newProjFields.get(currInput).set(bit - startField);
    }
    // for each input
    return new MultiJoin(multiJoin.getCluster(), multiJoin.getInputs(), multiJoin.getJoinFilter(), multiJoin.getRowType(), multiJoin.isFullOuterJoin(), multiJoin.getOuterJoinConditions(), multiJoin.getJoinTypes(), Lists.transform(newProjFields, ImmutableBitSet.FROM_BIT_SET), multiJoin.getJoinFieldRefCountsMap(), multiJoin.getPostJoinFilter());
}