/// <summary>
/// Creates groups and computes aggregate values for each group.
/// </summary>
/// <param name="equalityComparer"> Equality comparer where T is group key and computes internaly the hash for each row from the result table.</param>
/// <param name="resTable"> A result table from the matching clause.</param>
/// <param name="hasher"> Hasher of rows. </param>
/// <returns> Aggregate results. </returns>
private GroupByResults SingleThreadGroupBy(RowHasher hasher, RowEqualityComparerGroupKey equalityComparer, ITableResults resTable)
{
#region DECL
hasher.SetCache(equalityComparer.comparers);
var aggResults = AggregateListResults.CreateListResults(this.aggregates);
var groups = new Dictionary <GroupDictKey, int>(equalityComparer);
int position;
TableResults.RowProxy row;
GroupDictKey key;
#endregion DECL
for (int i = 0; i < resTable.NumberOfMatchedElements; i++)
{
row = resTable[i];
key = new GroupDictKey(hasher.Hash(in row), i); // It's a struct.
if (!groups.TryGetValue(key, out position))
{
position = groups.Count;
groups.Add(key, position);
}
for (int j = 0; j < aggregates.Length; j++)
{
aggregates[j].Apply(in row, aggResults[j], position);
}
}
return(new GroupByResultsList(groups, aggResults, resTable));
}
public GroupJob(Aggregate[] aggregates, RowEqualityComparerGroupKey comparer, RowHasher hasher, AggregateBucketResult[] spareBuckets, ITableResults resTable)
{
this.resTable = resTable;
comparer.resTable = this.resTable;
this.groups = new Dictionary <GroupDictKey, int>(comparer);
this.hasher = hasher;
this.spareBuckets = spareBuckets;
this.aggResults = AggregateListResults.CreateListResults(aggregates);
}
public GroupByJobMixListsBuckets(RowHasher hasher, RowEqualityComparerGroupKey comparer, Aggregate[] aggregates, ITableResults resTable, int start, int end, ConcurrentDictionary <GroupDictKey, AggregateBucketResult[]> globalGroups) : base(hasher, aggregates, resTable, start, end, globalGroups)
{
this.groups = new Dictionary <GroupDictKey, int>(comparer);
this.aggResults = AggregateListResults.CreateListResults(aggregates);
}
public GroupByJobLists(RowHasher hasher, RowEqualityComparerGroupKey comparer, Aggregate[] aggregates, ITableResults resTable, int start, int end) : base(hasher, comparer, aggregates, resTable, start, end)
{
this.groups = new Dictionary <GroupDictKey, int>(comparer);
this.aggResults = AggregateListResults.CreateListResults(aggregates);
}