コード例 #1
0
  public Double getPercentageOriginalRows(AggregateRelBase rel) {
    // REVIEW jvs 28-Mar-2006: The assumption here seems to be that
    // aggregation does not apply any filtering, so it does not modify the
    // percentage.  That's very much oversimplified.

    return RelMetadataQuery.getPercentageOriginalRows(rel.getChild());
  }
コード例 #2
0
 public Boolean areColumnsUnique(AggregateRelBase rel, BitSet columns, boolean ignoreNulls) {
   // group by keys form a unique key
   if (rel.getGroupCount() > 0) {
     BitSet groupKey = new BitSet();
     for (int i = 0; i < rel.getGroupCount(); i++) {
       groupKey.set(i);
     }
     return BitSets.contains(columns, groupKey);
   } else {
     // interpret an empty set as asking whether the aggregation is full
     // table (in which case it returns at most one row);
     // TODO jvs 1-Sept-2008:  apply this convention consistently
     // to other relational expressions, as well as to
     // RelMetadataQuery.getUniqueKeys
     return columns.isEmpty();
   }
 }