Interface SortInfo

All Known Implementing Classes:
MergeSortInfo

public interface SortInfo
This object provides performance information related to a sort. The information is accumulated during operations on a SortController() and then copied into this object and returned by a call to SortController.getSortInfo().
  • Method Summary

    Modifier and Type
    Method
    Description
    Return all information gathered about the sort.
  • Method Details

    • getAllSortInfo

      Properties getAllSortInfo(Properties prop) throws StandardException
      Return all information gathered about the sort.

      This routine returns a list of properties which contains all information gathered about the sort. If a Property is passed in, then that property list is appended to, otherwise a new property object is created and returned.

      Not all sorts may support all properties, if the property is not supported then it will not be returned. The following is a list of properties that may be returned: sortType - type of the sort being performed: internal external numRowsInput - the number of rows input to the sort. This number includes duplicates. numRowsOutput - the number of rows to be output by the sort. This number may be different from numRowsInput since duplicates may not be output. numMergeRuns - the number of merge runs for the sort. Applicable to external sorts only. Note: when a SortController is closed, numMergeRuns may increase by 1, to reflect the additional merge run that may be created for any data still in the sort buffer. mergeRunsSize - the size (number of rows) of each merge run for the sort. Applicable to external sorts only. e.g. [3,3,2] indicates 3 merge runs, where the first two runs have 3 rows each, and the last run has 2 rows. Note: when a SortController is closed, this vector may get an additional element, to reflect the additional merge run that may be created for any data still in the sort buffer. NOTE - this list will be expanded as more information about the sort is gathered and returned.

      Parameters:
      prop - Property list to fill in.
      Throws:
      StandardException - Standard exception policy.