// Group By Costs //
/// <summary>
/// Represents the cost to group data from an ordered stream
/// </summary>
/// <param name="RecordCount"></param>
/// <param name="BuildIndex"></param>
/// <returns></returns>
public static double OrderedGroupByCost(long RecordCount, bool BuildIndex)
{
return((double)RecordCount + (BuildIndex ? CostCalculator.IndexBuildCost(RecordCount) : 0));
}
/// <summary>
///
/// </summary>
/// <param name="ARecordCount"></param>
/// <param name="BRecordCount"></param>
/// <param name="BuildLeftIndex"></param>
/// <param name="BuildRightIndex"></param>
/// <returns></returns>
public static double SortMergeNestedLoopJoinCost(long ARecordCount, long BRecordCount, bool BuildLeftIndex, bool BuildRightIndex)
{
return((double)Math.Max(ARecordCount, BRecordCount)
+ (BuildLeftIndex ? CostCalculator.IndexBuildCost(ARecordCount) : 0)
+ (BuildRightIndex ? CostCalculator.IndexBuildCost(BRecordCount) : 0));
}
/// <summary>
/// Returns the cost for performing a quasi-nested loop join
/// </summary>
/// <param name="ARecordCount"></param>
/// <param name="BRecordCount"></param>
/// <param name="BuildRightIndex"></param>
/// <returns></returns>
public static double QuasiNestedLoopJoinCost(long ARecordCount, long BRecordCount, bool BuildRightIndex)
{
return(ARecordCount * CostCalculator.LogN(BRecordCount) + (BuildRightIndex ? CostCalculator.IndexBuildCost(BRecordCount) : 0));
}
/// <summary>
/// Returns the cost for building an index
/// </summary>
/// <param name="RecordCount"></param>
/// <returns></returns>
public static double IndexBuildCost(long RecordCount)
{
return(CostCalculator.SumLogI(RecordCount));
}
// Index Costs //
/// <summary>
/// Returns the cost for searching an index
/// </summary>
/// <param name="RecordCount"></param>
/// <returns></returns>
public static double IndexSeekCost(long RecordCount)
{
return(CostCalculator.LogN(RecordCount));
}
/// <summary>
/// Represents the cost to group by using a dictionary
/// </summary>
/// <param name="RecordCount"></param>
/// <returns></returns>
public static double DictionaryGroupByCost(long RecordCount)
{
return((double)RecordCount + CostCalculator.IndexBuildCost(RecordCount));
}