org.knime.base.node.preproc.groupby
Class BigGroupByTable

java.lang.Object
  org.knime.base.node.preproc.groupby.GroupByTable
      org.knime.base.node.preproc.groupby.BigGroupByTable

public class BigGroupByTable
extends GroupByTable

A data table that groups a given input table by the given columns and calculates the aggregation values of the remaining rows. Call the GroupByTable.getBufferedTable() method after instance creation to get the grouped table. If the enableHilite flag was set to true call the GroupByTable.getHiliteMapping() method to get the row key translation Map. Call the GroupByTable.getSkippedGroupsByColName() method to get a Map with all skipped groups or the GroupByTable.getSkippedGroupsMessage(int, int) for a appropriate warning message.

Author:

Tobias Koetter, University of Konstanz

Constructor Summary

BigGroupByTable(ExecutionContext exec, BufferedDataTable inDataTable, List<String> groupByCols, ColumnAggregator[] colAggregators, GlobalSettings globalSettings, boolean sortInMemory, boolean enableHilite, ColumnNamePolicy colNamePolicy, boolean retainOrder)
Constructor for class BigGroupByTable.

Method Summary

protected BufferedDataTable

createGroupByTable(ExecutionContext exec, BufferedDataTable table, DataTableSpec resultSpec, int[] groupColIdx)

Methods inherited from class org.knime.base.node.preproc.groupby.GroupByTable

addHiliteMapping, addSkippedGroup, appendOrderColumn, checkGroupCols, createGroupByTableSpec, createSkippedGroupName, getBufferedTable, getColAggregators, getGlobalSettings, getGroupCols, getHiliteMapping, getSkippedGroupsByColName, getSkippedGroupsMessage, isEnableHilite, isRetainOrder, isSortInMemory, sortTable

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BigGroupByTable

public BigGroupByTable(ExecutionContext exec,
                       BufferedDataTable inDataTable,
                       List<String> groupByCols,
                       ColumnAggregator[] colAggregators,
                       GlobalSettings globalSettings,
                       boolean sortInMemory,
                       boolean enableHilite,
                       ColumnNamePolicy colNamePolicy,
                       boolean retainOrder)
                throws CanceledExecutionException

Constructor for class BigGroupByTable.

Parameters:

exec - the ExecutionContext

inDataTable - the table to aggregate

groupByCols - the name of all columns to group by

colAggregators - the aggregation columns with the aggregation method to use in the order the columns should be appear in the result table numerical columns

globalSettings - the global settings

sortInMemory - true if the table should be sorted in the memory

enableHilite - true if a row key map should be maintained to enable hiliting

colNamePolicy - the ColumnNamePolicy for the aggregation columns

retainOrder - returns the row of the table in the same order as the input table if set to true

Throws:

CanceledExecutionException - if the user has canceled the execution

Method Detail

createGroupByTable

protected BufferedDataTable createGroupByTable(ExecutionContext exec,
                                               BufferedDataTable table,
                                               DataTableSpec resultSpec,
                                               int[] groupColIdx)
                                        throws CanceledExecutionException

Specified by:

createGroupByTable in class GroupByTable

Parameters:

exec - the ExecutionContext

table - the data table to aggregate

resultSpec - the result DataTableSpec

groupColIdx - the group column indices

Returns:

the aggregated input table

Throws:

CanceledExecutionException - if the operation has been canceled