Exemplo n.º 1
0
 public SortRel copy(
     RelTraitSet traitSet,
     RelNode newInput,
     RelCollation newCollation,
     RexNode offset,
     RexNode fetch) {
   assert traitSet.containsIfApplicable(Convention.NONE);
   return new SortRel(getCluster(), traitSet, newInput, newCollation, offset, fetch);
 }
Exemplo n.º 2
0
  /**
   * Creates a sorter.
   *
   * @param cluster Cluster this relational expression belongs to
   * @param traits Traits
   * @param child input relational expression
   * @param collation array of sort specifications
   * @param offset Expression for number of rows to discard before returning first row
   * @param fetch Expression for number of rows to fetch
   */
  public SortRel(
      RelOptCluster cluster,
      RelTraitSet traits,
      RelNode child,
      RelCollation collation,
      RexNode offset,
      RexNode fetch) {
    super(cluster, traits, child);
    this.collation = collation;
    this.offset = offset;
    this.fetch = fetch;

    assert traits.containsIfApplicable(collation) : "traits=" + traits + ", collation=" + collation;
    assert !(fetch == null && offset == null && collation.getFieldCollations().isEmpty())
        : "trivial sort";
    ImmutableList.Builder<RexNode> builder = ImmutableList.builder();
    for (RelFieldCollation field : collation.getFieldCollations()) {
      int index = field.getFieldIndex();
      builder.add(cluster.getRexBuilder().makeInputRef(child, index));
    }
    fieldExps = builder.build();
  }