org.apache.calcite.rel.RelNode.estimateRowCount()方法的使用及代码示例

x33g5p2x  于2022-01-29 转载在 其他  
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本文整理了Java中org.apache.calcite.rel.RelNode.estimateRowCount方法的一些代码示例，展示了RelNode.estimateRowCount的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。RelNode.estimateRowCount方法的具体详情如下：
包路径：org.apache.calcite.rel.RelNode
类名称：RelNode
方法名：estimateRowCount

RelNode.estimateRowCount介绍

[英]Returns an estimate of the number of rows this relational expression will return.

NOTE jvs 29-Mar-2006: Don't call this method directly. Instead, use RelMetadataQuery#getRowCount, which gives plugins a chance to override the rel's default ideas about row count.
[中]返回此关系表达式将返回的行数的估计值。
注意jvs 2006年3月29日：不要直接调用此方法。相反，使用RelMetadataQuery#getRowCount，这让插件有机会覆盖rel关于行数的默认想法。

代码示例

代码示例来源：origin: apache/drill

public JdbcPrel(RelOptCluster cluster, RelTraitSet traitSet, JdbcIntermediatePrel prel) {
 super(cluster, traitSet);
 final RelNode input = prel.getInput();
 rows = input.estimateRowCount(cluster.getMetadataQuery());
 convention = (DrillJdbcConvention) input.getTraitSet().getTrait(ConventionTraitDef.INSTANCE);
 // generate sql for tree.
 final SqlDialect dialect = convention.getPlugin().getDialect();
 final JdbcImplementor jdbcImplementor = new JdbcImplementor(
   dialect,
   (JavaTypeFactory) getCluster().getTypeFactory());
 final JdbcImplementor.Result result =
   jdbcImplementor.visitChild(0, input.accept(new SubsetRemover()));
 sql = result.asStatement().toSqlString(dialect).getSql();
 rowType = input.getRowType();
}

代码示例来源：origin: dremio/dremio-oss

@Override
public double estimateRowCount(RelMetadataQuery mq) {
 return input.estimateRowCount(mq);
}

代码示例来源：origin: org.apache.calcite/calcite-core

/** Catch-all implementation for
 * {@link BuiltInMetadata.RowCount#getRowCount()},
 * invoked using reflection.
 *
 * @see org.apache.calcite.rel.metadata.RelMetadataQuery#getRowCount(RelNode)
 */
public Double getRowCount(RelNode rel, RelMetadataQuery mq) {
 return rel.estimateRowCount(mq);
}

代码示例来源：origin: Qihoo360/Quicksql

/** Catch-all implementation for
 * {@link BuiltInMetadata.RowCount#getRowCount()},
 * invoked using reflection.
 *
 * @see org.apache.calcite.rel.metadata.RelMetadataQuery#getRowCount(RelNode)
 */
public Double getRowCount(RelNode rel, RelMetadataQuery mq) {
 return rel.estimateRowCount(mq);
}

代码示例来源：origin: Qihoo360/Quicksql

@Override public double estimateRowCount(RelMetadataQuery mq) {
 final double leftRowCount = left.estimateRowCount(mq);
 final double rightRowCount = right.estimateRowCount(mq);
 return Math.max(leftRowCount, rightRowCount);
}

代码示例来源：origin: org.apache.calcite/calcite-core

@Override public double estimateRowCount(RelMetadataQuery mq) {
 final double leftRowCount = left.estimateRowCount(mq);
 final double rightRowCount = right.estimateRowCount(mq);
 return Math.max(leftRowCount, rightRowCount);
}

代码示例来源：origin: org.apache.drill.exec/drill-java-exec

@Override
public double estimateRowCount(RelMetadataQuery mq) {
 return this.getLeft().estimateRowCount(mq) * this.getRight().estimateRowCount(mq);
}

代码示例来源：origin: org.apache.drill.exec/drill-java-exec

@Override
public double estimateRowCount(RelMetadataQuery mq) {
 if (this.condition.isAlwaysTrue()) {
  return joinRowFactor * this.getLeft().estimateRowCount(mq) * this.getRight().estimateRowCount(mq);
 } else {
  return joinRowFactor * Math.max(this.getLeft().estimateRowCount(mq), this.getRight().estimateRowCount(mq));
 }
}

代码示例来源：origin: dremio/dremio-oss

public Double getRowCount(JdbcRelBase jdbc, RelMetadataQuery mq) {
 return jdbc.getSubTree().estimateRowCount(mq);
}

代码示例来源：origin: org.apache.calcite/calcite-core

@Override public RelOptCost computeSelfCost(RelOptPlanner planner,
  RelMetadataQuery mq) {
 // We assume that the inputs are sorted. The price of sorting them has
 // already been paid. The cost of the join is therefore proportional to the
 // input and output size.
 final double rightRowCount = right.estimateRowCount(mq);
 final double leftRowCount = left.estimateRowCount(mq);
 final double rowCount = mq.getRowCount(this);
 final double d = leftRowCount + rightRowCount + rowCount;
 return planner.getCostFactory().makeCost(d, 0, 0);
}

代码示例来源：origin: Qihoo360/Quicksql

@Override public RelOptCost computeSelfCost(RelOptPlanner planner,
  RelMetadataQuery mq) {
 // We assume that the inputs are sorted. The price of sorting them has
 // already been paid. The cost of the join is therefore proportional to the
 // input and output size.
 final double rightRowCount = right.estimateRowCount(mq);
 final double leftRowCount = left.estimateRowCount(mq);
 final double rowCount = mq.getRowCount(this);
 final double d = leftRowCount + rightRowCount + rowCount;
 return planner.getCostFactory().makeCost(d, 0, 0);
}

代码示例来源：origin: dremio/dremio-oss

private Double getDistinctRowCountFromEstimateRowCount(RelNode rel, RelMetadataQuery mq, ImmutableBitSet groupKey, RexNode predicate) {
  final int groupKeySize = groupKey.cardinality();
  return rel.estimateRowCount(mq) * (1.0 - Math.pow(0.9, groupKeySize)) * RelMdUtil.guessSelectivity(predicate);
 }
}

代码示例来源：origin: org.apache.drill.exec/drill-java-exec

@Override
public double estimateRowCount(RelMetadataQuery mq) {
 int off = offset != null? RexLiteral.intValue(offset): 0;
 if (fetch == null) {
  // If estimated rowcount is less than offset return 0
  return Math.max(0, getInput().estimateRowCount(mq) - off);
 } else {
  int f = RexLiteral.intValue(fetch);
  return off + f;
 }
}

代码示例来源：origin: org.apache.calcite/calcite-core

@Override public RelOptCost computeSelfCost(RelOptPlanner planner,
  RelMetadataQuery mq) {
 double rowCount = mq.getRowCount(this);
 // Right-hand input is the "build", and hopefully small, input.
 final double rightRowCount = right.estimateRowCount(mq);
 final double leftRowCount = left.estimateRowCount(mq);
 if (Double.isInfinite(leftRowCount)) {
  rowCount = leftRowCount;
 } else {
  rowCount += Util.nLogN(leftRowCount);
 }
 if (Double.isInfinite(rightRowCount)) {
  rowCount = rightRowCount;
 } else {
  rowCount += rightRowCount;
 }
 return planner.getCostFactory().makeCost(rowCount, 0, 0).multiplyBy(.01d);
}

代码示例来源：origin: Qihoo360/Quicksql

@Override public RelOptCost computeSelfCost(RelOptPlanner planner,
  RelMetadataQuery mq) {
 double rowCount = mq.getRowCount(this);
 // Right-hand input is the "build", and hopefully small, input.
 final double rightRowCount = right.estimateRowCount(mq);
 final double leftRowCount = left.estimateRowCount(mq);
 if (Double.isInfinite(leftRowCount)) {
  rowCount = leftRowCount;
 } else {
  rowCount += Util.nLogN(leftRowCount);
 }
 if (Double.isInfinite(rightRowCount)) {
  rowCount = rightRowCount;
 } else {
  rowCount += rightRowCount;
 }
 return planner.getCostFactory().makeCost(rowCount, 0, 0).multiplyBy(.01d);
}

代码示例来源：origin: Qihoo360/Quicksql

@Override public RelOptCost computeSelfCost(RelOptPlanner planner,
  RelMetadataQuery mq) {
 double rowCount = mq.getRowCount(this);
 // Joins can be flipped, and for many algorithms, both versions are viable
 // and have the same cost. To make the results stable between versions of
 // the planner, make one of the versions slightly more expensive.
 switch (joinType) {
 case RIGHT:
  rowCount = addEpsilon(rowCount);
  break;
 default:
  if (left.getId() > right.getId()) {
   rowCount = addEpsilon(rowCount);
  }
 }
 final double rightRowCount = right.estimateRowCount(mq);
 final double leftRowCount = left.estimateRowCount(mq);
 if (Double.isInfinite(leftRowCount)) {
  rowCount = leftRowCount;
 }
 if (Double.isInfinite(rightRowCount)) {
  rowCount = rightRowCount;
 }
 return planner.getCostFactory().makeCost(rowCount, 0, 0);
}

代码示例来源：origin: Qihoo360/Quicksql

@Override public RelOptCost computeSelfCost(RelOptPlanner planner,
   RelMetadataQuery mq) {
  double rowCount = mq.getRowCount(this);

  final double rightRowCount = right.estimateRowCount(mq);
  final double leftRowCount = left.estimateRowCount(mq);
  if (Double.isInfinite(leftRowCount) || Double.isInfinite(rightRowCount)) {
   return planner.getCostFactory().makeInfiniteCost();
  }

  Double restartCount = mq.getRowCount(getLeft());
  // RelMetadataQuery.getCumulativeCost(getRight()); does not work for
  // RelSubset, so we ask planner to cost-estimate right relation
  RelOptCost rightCost = planner.getCost(getRight(), mq);
  RelOptCost rescanCost =
    rightCost.multiplyBy(Math.max(1.0, restartCount - 1));

  return planner.getCostFactory().makeCost(
    rowCount /* generate results */ + leftRowCount /* scan left results */,
    0, 0).plus(rescanCost);
 }
}

代码示例来源：origin: org.apache.calcite/calcite-core

@Override public RelOptCost computeSelfCost(RelOptPlanner planner,
   RelMetadataQuery mq) {
  double rowCount = mq.getRowCount(this);

  final double rightRowCount = right.estimateRowCount(mq);
  final double leftRowCount = left.estimateRowCount(mq);
  if (Double.isInfinite(leftRowCount) || Double.isInfinite(rightRowCount)) {
   return planner.getCostFactory().makeInfiniteCost();
  }

  Double restartCount = mq.getRowCount(getLeft());
  // RelMetadataQuery.getCumulativeCost(getRight()); does not work for
  // RelSubset, so we ask planner to cost-estimate right relation
  RelOptCost rightCost = planner.getCost(getRight(), mq);
  RelOptCost rescanCost =
    rightCost.multiplyBy(Math.max(1.0, restartCount - 1));

  return planner.getCostFactory().makeCost(
    rowCount /* generate results */ + leftRowCount /* scan left results */,
    0, 0).plus(rescanCost);
 }
}

代码示例来源：origin: org.apache.drill.exec/drill-java-exec

@Override
public Prel visitJoin(JoinPrel prel, Double value) throws RuntimeException {
 JoinPrel newJoin = (JoinPrel) visitPrel(prel, value);
 if (prel instanceof HashJoinPrel &&
   !((HashJoinPrel) prel).isRowKeyJoin() /* don't swap for rowkey joins */) {
  // Mark left/right is swapped, when INNER hash join's left row count < ( 1+ margin factor) right row count.
  RelMetadataQuery mq = newJoin.getCluster().getMetadataQuery();
  if (newJoin.getLeft().estimateRowCount(mq) < (1 + value) * newJoin.getRight().estimateRowCount(mq) &&
    newJoin.getJoinType() == JoinRelType.INNER && !newJoin.isSemiJoin()) {
   ((HashJoinPrel) newJoin).setSwapped(true);
  }
 }
 return newJoin;
}

代码示例来源：origin: org.apache.drill.exec/drill-java-exec

protected boolean create2PhasePlan(RelOptRuleCall call, DrillAggregateRel aggregate) {
 PlannerSettings settings = PrelUtil.getPlannerSettings(call.getPlanner());
 RelNode child = call.rel(0).getInputs().get(0);
 boolean smallInput =
   child.estimateRowCount(child.getCluster().getMetadataQuery()) < settings.getSliceTarget();
 if (!settings.isMultiPhaseAggEnabled() || settings.isSingleMode()
   // Can override a small child - e.g., for testing with a small table
   || (smallInput && !settings.isForce2phaseAggr())) {
  return false;
 }
 for (AggregateCall aggCall : aggregate.getAggCallList()) {
  String name = aggCall.getAggregation().getName();
  if (!(name.equals(SqlKind.SUM.name())
    || name.equals(SqlKind.MIN.name())
    || name.equals(SqlKind.MAX.name())
    || name.equals(SqlKind.COUNT.name())
    || name.equals("$SUM0"))) {
   return false;
  }
 }
 return true;
}

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