示例#1
0
  /**
   * Combines the join filters from the left and right inputs (if they are MultiJoinRels) with the
   * join filter in the joinrel into a single AND'd join filter, unless the inputs correspond to
   * null generating inputs in an outer join
   *
   * @param joinRel join rel
   * @param left left child of the joinrel
   * @param right right child of the joinrel
   * @return combined join filters AND'd together
   */
  private RexNode combineJoinFilters(JoinRel joinRel, RelNode left, RelNode right) {
    RexBuilder rexBuilder = joinRel.getCluster().getRexBuilder();
    JoinRelType joinType = joinRel.getJoinType();

    // first need to adjust the RexInputs of the right child, since
    // those need to shift over to the right
    RexNode rightFilter = null;
    if (canCombine(right, joinType.generatesNullsOnRight())) {
      MultiJoinRel multiJoin = (MultiJoinRel) right;
      rightFilter = shiftRightFilter(joinRel, left, multiJoin, multiJoin.getJoinFilter());
    }

    // AND the join condition if this isn't a left or right outer join;
    // in those cases, the outer join condition is already tracked
    // separately
    RexNode newFilter = null;
    if ((joinType != JoinRelType.LEFT) && (joinType != JoinRelType.RIGHT)) {
      newFilter = joinRel.getCondition();
    }
    if (canCombine(left, joinType.generatesNullsOnLeft())) {
      RexNode leftFilter = ((MultiJoinRel) left).getJoinFilter();
      newFilter = RelOptUtil.andJoinFilters(rexBuilder, newFilter, leftFilter);
    }
    newFilter = RelOptUtil.andJoinFilters(rexBuilder, newFilter, rightFilter);

    return newFilter;
  }
示例#2
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  public void onMatch(RelOptRuleCall call) {
    JoinRel origJoinRel = (JoinRel) call.rels[0];

    RelNode left = call.rels[1];
    RelNode right = call.rels[2];

    // combine the children MultiJoinRel inputs into an array of inputs
    // for the new MultiJoinRel
    List<BitSet> projFieldsList = new ArrayList<BitSet>();
    List<int[]> joinFieldRefCountsList = new ArrayList<int[]>();
    RelNode[] newInputs =
        combineInputs(origJoinRel, left, right, projFieldsList, joinFieldRefCountsList);

    // combine the outer join information from the left and right
    // inputs, and include the outer join information from the current
    // join, if it's a left/right outer join
    RexNode[] newOuterJoinConds = new RexNode[newInputs.length];
    JoinRelType[] joinTypes = new JoinRelType[newInputs.length];
    combineOuterJoins(origJoinRel, newInputs, left, right, newOuterJoinConds, joinTypes);

    // pull up the join filters from the children MultiJoinRels and
    // combine them with the join filter associated with this JoinRel to
    // form the join filter for the new MultiJoinRel
    RexNode newJoinFilter = combineJoinFilters(origJoinRel, left, right);

    // add on the join field reference counts for the join condition
    // associated with this JoinRel
    Map<Integer, int[]> newJoinFieldRefCountsMap = new HashMap<Integer, int[]>();
    addOnJoinFieldRefCounts(
        newInputs,
        origJoinRel.getRowType().getFieldCount(),
        origJoinRel.getCondition(),
        joinFieldRefCountsList,
        newJoinFieldRefCountsMap);

    RexNode newPostJoinFilter = combinePostJoinFilters(origJoinRel, left, right);

    RelNode multiJoin =
        new MultiJoinRel(
            origJoinRel.getCluster(),
            newInputs,
            newJoinFilter,
            origJoinRel.getRowType(),
            (origJoinRel.getJoinType() == JoinRelType.FULL),
            newOuterJoinConds,
            joinTypes,
            projFieldsList.toArray(new BitSet[projFieldsList.size()]),
            newJoinFieldRefCountsMap,
            newPostJoinFilter);

    call.transformTo(multiJoin);
  }
  // implement RelOptRule
  public void onMatch(RelOptRuleCall call) {
    ProjectRel origProj = call.rel(0);
    JoinRel joinRel = call.rel(1);

    // locate all fields referenced in the projection and join condition;
    // determine which inputs are referenced in the projection and
    // join condition; if all fields are being referenced and there are no
    // special expressions, no point in proceeding any further
    PushProjector pushProject =
        new PushProjector(origProj, joinRel.getCondition(), joinRel, preserveExprCondition);
    if (pushProject.locateAllRefs()) {
      return;
    }

    // create left and right projections, projecting only those
    // fields referenced on each side
    RelNode leftProjRel = pushProject.createProjectRefsAndExprs(joinRel.getLeft(), true, false);
    RelNode rightProjRel = pushProject.createProjectRefsAndExprs(joinRel.getRight(), true, true);

    // convert the join condition to reference the projected columns
    RexNode newJoinFilter = null;
    int[] adjustments = pushProject.getAdjustments();
    if (joinRel.getCondition() != null) {
      List<RelDataTypeField> projJoinFieldList = new ArrayList<RelDataTypeField>();
      projJoinFieldList.addAll(joinRel.getSystemFieldList());
      projJoinFieldList.addAll(leftProjRel.getRowType().getFieldList());
      projJoinFieldList.addAll(rightProjRel.getRowType().getFieldList());
      newJoinFilter =
          pushProject.convertRefsAndExprs(joinRel.getCondition(), projJoinFieldList, adjustments);
    }

    // create a new joinrel with the projected children
    JoinRel newJoinRel =
        new JoinRel(
            joinRel.getCluster(),
            leftProjRel,
            rightProjRel,
            newJoinFilter,
            joinRel.getJoinType(),
            Collections.<String>emptySet(),
            joinRel.isSemiJoinDone(),
            joinRel.getSystemFieldList());

    // put the original project on top of the join, converting it to
    // reference the modified projection list
    ProjectRel topProject = pushProject.createNewProject(newJoinRel, adjustments);

    call.transformTo(topProject);
  }
        public void onMatch(RelOptRuleCall call) {
          JoinRel join = (JoinRel) call.rels[0];
          List<RexNode> expList = new ArrayList<RexNode>(Arrays.asList(join.getChildExps()));
          if (reduceExpressions(join, expList)) {
            call.transformTo(
                new JoinRel(
                    join.getCluster(),
                    join.getLeft(),
                    join.getRight(),
                    expList.get(0),
                    join.getJoinType(),
                    join.getVariablesStopped()));

            // New plan is absolutely better than old plan.
            call.getPlanner().setImportance(join, 0.0);
          }
        }
示例#5
0
  /**
   * Combines the post-join filters from the left and right inputs (if they are MultiJoinRels) into
   * a single AND'd filter.
   *
   * @param joinRel the original JoinRel
   * @param left left child of the JoinRel
   * @param right right child of the JoinRel
   * @return combined post-join filters AND'd together
   */
  private RexNode combinePostJoinFilters(JoinRel joinRel, RelNode left, RelNode right) {
    RexNode rightPostJoinFilter = null;
    if (right instanceof MultiJoinRel) {
      rightPostJoinFilter =
          shiftRightFilter(
              joinRel, left, (MultiJoinRel) right, ((MultiJoinRel) right).getPostJoinFilter());
    }

    RexNode leftPostJoinFilter = null;
    if (left instanceof MultiJoinRel) {
      leftPostJoinFilter = ((MultiJoinRel) left).getPostJoinFilter();
    }

    if ((leftPostJoinFilter == null) && (rightPostJoinFilter == null)) {
      return null;
    } else {
      return RelOptUtil.andJoinFilters(
          joinRel.getCluster().getRexBuilder(), leftPostJoinFilter, rightPostJoinFilter);
    }
  }
示例#6
0
  /**
   * Shifts a filter originating from the right child of the JoinRel to the right, to reflect the
   * filter now being applied on the resulting MultiJoinRel.
   *
   * @param joinRel the original JoinRel
   * @param left the left child of the JoinRel
   * @param right the right child of the JoinRel
   * @param rightFilter the filter originating from the right child
   * @return the adjusted right filter
   */
  private RexNode shiftRightFilter(
      JoinRel joinRel, RelNode left, MultiJoinRel right, RexNode rightFilter) {
    if (rightFilter == null) {
      return null;
    }

    int nFieldsOnLeft = left.getRowType().getFields().length;
    int nFieldsOnRight = right.getRowType().getFields().length;
    int[] adjustments = new int[nFieldsOnRight];
    for (int i = 0; i < nFieldsOnRight; i++) {
      adjustments[i] = nFieldsOnLeft;
    }
    rightFilter =
        rightFilter.accept(
            new RelOptUtil.RexInputConverter(
                joinRel.getCluster().getRexBuilder(),
                right.getRowType().getFields(),
                joinRel.getRowType().getFields(),
                adjustments));
    return rightFilter;
  }