org.apache.derby.impl.sql.execute
Class DistinctScanResultSet

java.lang.Object
  extended byorg.apache.derby.impl.sql.execute.BasicNoPutResultSetImpl
      extended byorg.apache.derby.impl.sql.execute.NoPutResultSetImpl
          extended byorg.apache.derby.impl.sql.execute.HashScanResultSet
              extended byorg.apache.derby.impl.sql.execute.DistinctScanResultSet
All Implemented Interfaces:
CursorResultSet, NoPutResultSet, ResultSet, RowLocationRetRowSource, RowSource

public class DistinctScanResultSet
extends HashScanResultSet

Eliminates duplicates while scanning the underlying conglomerate. (Assumes no predicates, for now.)

Author:
jerry

Field Summary
(package private)  java.util.Enumeration element
           
 
Fields inherited from class org.apache.derby.impl.sql.execute.HashScanResultSet
activation, beginTime, candidate, checkGM, checkNullCols, clonedExecRow, closeTime, cncLen, compactRow, constructorTime, currentRow, DEFAULT_INITIAL_CAPACITY, DEFAULT_LOADFACTOR, DEFAULT_MAX_CAPACITY, eliminateDuplicates, endExecutionTime, finished, firstNext, forUpdate, hashtable, hashtableSize, heapConglomerate, indent, indexName, isConstraint, isolationLevel, isOpen, isTopResultSet, keyColumns, lcc, lockMode, nextQualifiers, nextTime, numOpens, openTime, optimizerEstimatedCost, optimizerEstimatedRowCount, resultDescription, resultSetNumber, rowsFiltered, rowsSeen, scanProperties, scanQualifiers, scoci, sourceDepth, startExecutionTime, startPositionString, stopPositionString, subIndent, subqueryTrackingArray, tableName, targetResultSet
 
Fields inherited from interface org.apache.derby.iapi.sql.ResultSet
CURRENT_RESULTSET_ONLY, ENTIRE_RESULTSET_TREE, ISAFTERLAST, ISBEFOREFIRST, ISFIRST, ISLAST
 
Fields inherited from interface org.apache.derby.iapi.sql.execute.NoPutResultSet
ABSOLUTE, FIRST, LAST, NEXT, PREVIOUS, RELATIVE
 
Constructor Summary
DistinctScanResultSet(long conglomId, StaticCompiledOpenConglomInfo scoci, Activation activation, GeneratedMethod resultRowAllocator, int resultSetNumber, int hashKeyItem, java.lang.String tableName, java.lang.String indexName, boolean isConstraint, int colRefItem, int lockMode, boolean tableLocked, int isolationLevel, double optimizerEstimatedRowCount, double optimizerEstimatedCost, GeneratedMethod closeCleanup)
           
 
Method Summary
 ExecRow getNextRowCore()
          Return the next row (if any) from the scan (if open).
 
Methods inherited from class org.apache.derby.impl.sql.execute.HashScanResultSet
addWarning, attachStatementContext, checkRowPosition, cleanUp, clearCurrentRow, clearOrderableCache, close, closeRowSource, dumpTimeStats, finish, finishAndRTS, getAbsoluteRow, getAutoGeneratedKeysResultset, getBeginExecutionTimestamp, getCompactRow, getCurrentRow, getCurrentTimeMillis, getCursorName, getElapsedMillis, getEndExecutionTimestamp, getEstimatedRowCount, getExecuteTime, getExecutionFactory, getFirstRow, getLanguageConnectionContext, getLastRow, getNextRow, getNextRowFromRowSource, getPointOfAttachment, getPreviousRow, getRelativeRow, getResultDescription, getRowLocation, getRowNumber, getScanIsolationLevel, getScanProperties, getSubqueryTrackingArray, getTimeSpent, getTransactionController, getValidColumns, getWarnings, isClosed, isForUpdate, markAsTopResultSet, modifiedRowCount, needsRowLocation, needsToClone, open, openCore, printQualifiers, printStartPosition, printStopPosition, reopenCore, requiresRelocking, resultSetNumber, returnsRows, rowLocation, setAfterLastRow, setBeforeFirstRow, setCheckConstraints, setCompactRow, setCompatRow, setCurrentRow, setHeapConglomerate, setNeedsRowLocation, setTargetResultSet, skipRow, skipScan
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.apache.derby.iapi.sql.ResultSet
checkRowPosition, cleanUp, finish, getAbsoluteRow, getAutoGeneratedKeysResultset, getBeginExecutionTimestamp, getCursorName, getEndExecutionTimestamp, getExecuteTime, getFirstRow, getLastRow, getNextRow, getPreviousRow, getRelativeRow, getResultDescription, getRowNumber, getSubqueryTrackingArray, getWarnings, isClosed, modifiedRowCount, open, returnsRows, setAfterLastRow, setBeforeFirstRow
 

Field Detail

element

java.util.Enumeration element
Constructor Detail

DistinctScanResultSet

public DistinctScanResultSet(long conglomId,
                             StaticCompiledOpenConglomInfo scoci,
                             Activation activation,
                             GeneratedMethod resultRowAllocator,
                             int resultSetNumber,
                             int hashKeyItem,
                             java.lang.String tableName,
                             java.lang.String indexName,
                             boolean isConstraint,
                             int colRefItem,
                             int lockMode,
                             boolean tableLocked,
                             int isolationLevel,
                             double optimizerEstimatedRowCount,
                             double optimizerEstimatedCost,
                             GeneratedMethod closeCleanup)
                      throws StandardException
Method Detail

getNextRowCore

public ExecRow getNextRowCore()
                       throws StandardException
Return the next row (if any) from the scan (if open).

Specified by:
getNextRowCore in interface NoPutResultSet
Overrides:
getNextRowCore in class HashScanResultSet
Throws:
StandardException - thrown on failure to get next row

Built on Mon 2007-06-04 09:58:47+0400, from revision ???

Apache Derby V10.1 Engine Documentation - Copyright © 1997,2005 The Apache Software Foundation or its licensors, as applicable.