org.apache.derby.impl.sql.execute

Class SetOpResultSet

java.lang.Object

org.apache.derby.impl.sql.execute.BasicNoPutResultSetImpl

org.apache.derby.impl.sql.execute.NoPutResultSetImpl

org.apache.derby.impl.sql.execute.SetOpResultSet

All Implemented Interfaces:

CursorResultSet, NoPutResultSet, ResultSet, RowLocationRetRowSource, RowSource

class SetOpResultSet
extends NoPutResultSetImpl
implements CursorResultSet

Takes the result set produced by an ordered UNION ALL of two tagged result sets and produces the INTERSECT or EXCEPT of the two input result sets. This also projects out the tag, the last column of the input rows.

Field Summary

Fields

Modifier and Type	Field and Description
private Activation	activation
private boolean	all
private int[]	intermediateOrderByColumns
private int[]	intermediateOrderByDirection
private boolean[]	intermediateOrderByNullsLow
private ExecRow	leftInputRow
private NoPutResultSet	leftSource
private int	opType
private DataValueDescriptor[]	prevCols
private int	resultSetNumber
private ExecRow	rightInputRow
private NoPutResultSet	rightSource
private int	rowsReturned
private int	rowsSeenLeft
private int	rowsSeenRight

Fields inherited from class org.apache.derby.impl.sql.execute.NoPutResultSetImpl

checkNullCols, clonedExecRow, cncLen, targetResultSet

Fields inherited from class org.apache.derby.impl.sql.execute.BasicNoPutResultSetImpl

beginTime, closeTime, compactRow, constructorTime, currentRow, endExecutionTime, finished, isOpen, isTopResultSet, nextTime, numOpens, openTime, optimizerEstimatedCost, optimizerEstimatedRowCount, resultDescription, rowsFiltered, rowsSeen, startExecutionTime, subqueryTrackingArray

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

Constructors

Constructor and Description
SetOpResultSet(NoPutResultSet leftSource, NoPutResultSet rightSource, Activation activation, int resultSetNumber, long optimizerEstimatedRowCount, double optimizerEstimatedCost, int opType, boolean all, int intermediateOrderByColumnsSavedObject, int intermediateOrderByDirectionSavedObject, int intermediateOrderByNullsLowSavedObject)

Method Summary

Modifier and Type	Method and Description
private void	advanceRightPastDuplicates(DataValueDescriptor[] leftColumns)
void	close() If the result set has been opened, close the currently open source.
private int	compare(DataValueDescriptor[] leftCols, DataValueDescriptor[] rightCols)
void	finish() Tells the system that there will be no more access to any database information via this result set; in particular, no more calls to open().
ExecRow	getCurrentRow() Returns the current row of the result set.
NoPutResultSet	getLeftSourceInput() Return the left source input of this SetOpResultSet
ExecRow	getNextRowCore() Return the requested values computed from the next row (if any) for which the restriction evaluates to true.
int	getOpType() Return the set operation of this SetOpResultSet
int	getResultSetNumber() Return the result set number
NoPutResultSet	getRightSourceInput() Return the right source input of this SetOpResultSet
RowLocation	getRowLocation() Returns the row location of the current base table row of the cursor.
int	getRowsReturned() Return the number of rows returned from the result set
int	getRowsSeenLeft() Return the number of rows seen on the left source input
int	getRowsSeenRight() Return the number of rows seen on the right source input
long	getTimeSpent(int type) Return the total amount of time spent in this ResultSet
private boolean	isDuplicate(DataValueDescriptor[] curColumns)
void	openCore() open the first source.

Methods inherited from class org.apache.derby.impl.sql.execute.NoPutResultSetImpl

clearCurrentRow, clearOrderableCache, closeRowSource, getCursorName, getNextRowFromRowSource, getResultDescription, getValidColumns, isForUpdate, markRowAsDeleted, needsRowLocation, needsToClone, positionScanAtRowLocation, printQualifiers, resultSetNumber, rowLocation, setCurrentRow, setNeedsRowLocation, setTargetResultSet, skipRow, skipScan, updateRow

Methods inherited from class org.apache.derby.impl.sql.execute.BasicNoPutResultSetImpl

addWarning, attachStatementContext, checkCancellationFlag, checkRowPosition, cleanUp, dumpTimeStats, finishAndRTS, getAbsoluteRow, getActivation, getAutoGeneratedKeysResultset, getBeginExecutionTimestamp, getCompactRow, getCurrentTimeMillis, getElapsedMillis, getEndExecutionTimestamp, getEstimatedRowCount, getExecuteTime, getExecutionFactory, getFirstRow, getLanguageConnectionContext, getLastRow, getNextRow, getPointOfAttachment, getPreviousRow, getRelativeRow, getRowNumber, getScanIsolationLevel, getSubqueryTrackingArray, getTransactionController, getWarnings, isClosed, isXplainOnlyMode, markAsTopResultSet, modifiedRowCount, open, recordConstructorTime, reopenCore, requiresRelocking, returnsRows, setAfterLastRow, setBeforeFirstRow, setCompactRow, setCompatRow

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

addWarning, checkRowPosition, cleanUp, clearCurrentRow, getAbsoluteRow, getActivation, getAutoGeneratedKeysResultset, getBeginExecutionTimestamp, getCursorName, getEndExecutionTimestamp, getExecuteTime, getFirstRow, getLastRow, getNextRow, getPreviousRow, getRelativeRow, getResultDescription, getRowNumber, getSubqueryTrackingArray, getWarnings, isClosed, modifiedRowCount, open, returnsRows, setAfterLastRow, setBeforeFirstRow

Field Detail

leftSource

private final NoPutResultSet leftSource

rightSource

private final NoPutResultSet rightSource

activation

private final Activation activation

opType

private final int opType

all

private final boolean all

resultSetNumber

private final int resultSetNumber

prevCols

private DataValueDescriptor[] prevCols

leftInputRow

private ExecRow leftInputRow

rightInputRow

private ExecRow rightInputRow

intermediateOrderByColumns

private final int[] intermediateOrderByColumns

intermediateOrderByDirection

private final int[] intermediateOrderByDirection

intermediateOrderByNullsLow

private final boolean[] intermediateOrderByNullsLow

rowsSeenLeft

private int rowsSeenLeft

rowsSeenRight

private int rowsSeenRight

rowsReturned

private int rowsReturned

Constructor Detail

SetOpResultSet

SetOpResultSet(NoPutResultSet leftSource,
               NoPutResultSet rightSource,
               Activation activation,
               int resultSetNumber,
               long optimizerEstimatedRowCount,
               double optimizerEstimatedCost,
               int opType,
               boolean all,
               int intermediateOrderByColumnsSavedObject,
               int intermediateOrderByDirectionSavedObject,
               int intermediateOrderByNullsLowSavedObject)

Method Detail

openCore

public void openCore()
              throws StandardException

open the first source.

Specified by:

openCore in interface NoPutResultSet

Throws:

StandardException - thrown on failure

getNextRowCore

public ExecRow getNextRowCore()
                       throws StandardException

Description copied from interface: NoPutResultSet

Return the requested values computed from the next row (if any) for which the restriction evaluates to true.

restriction and projection parameters are evaluated for each row.

Specified by:

getNextRowCore in interface NoPutResultSet

Specified by:

getNextRowCore in class BasicNoPutResultSetImpl

Returns:

the next row of the intersect or except, null if there is none

Throws:

StandardException - thrown on failure

See Also:

NoPutResultSet.getNextRowCore()

advanceRightPastDuplicates

private void advanceRightPastDuplicates(DataValueDescriptor[] leftColumns)
                                 throws StandardException

Throws:

StandardException

compare

private int compare(DataValueDescriptor[] leftCols,
                    DataValueDescriptor[] rightCols)
             throws StandardException

Throws:

StandardException

isDuplicate

private boolean isDuplicate(DataValueDescriptor[] curColumns)
                     throws StandardException

Throws:

StandardException

getCurrentRow

public ExecRow getCurrentRow()

Description copied from interface: CursorResultSet

Returns the current row of the result set. REMIND: eventually, this will only return the current row for result sets that need to return it; either some field in the activation or a parameter in the constructor will be used to signal that this needs to function. This will let us limit the number of live objects we are holding on to.

Specified by:

getCurrentRow in interface CursorResultSet

Returns:

the last row returned by getNextRow. null if closed.

close

public void close()
           throws StandardException

If the result set has been opened, close the currently open source.

Specified by:

close in interface ResultSet

Overrides:

close in class NoPutResultSetImpl

Throws:

StandardException - thrown on error

finish

public void finish()
            throws StandardException

Description copied from interface: ResultSet

Tells the system that there will be no more access to any database information via this result set; in particular, no more calls to open(). Will close the result set if it is not already closed.

Specified by:

finish in interface ResultSet

Overrides:

finish in class BasicNoPutResultSetImpl

Throws:

StandardException - on error

getTimeSpent

public long getTimeSpent(int type)

Return the total amount of time spent in this ResultSet

Specified by:

getTimeSpent in interface ResultSet

Parameters:

type - CURRENT_RESULTSET_ONLY - time spent only in this ResultSet ENTIRE_RESULTSET_TREE - time spent in this ResultSet and below.

Returns:

long The total amount of time spent (in milliseconds).

getRowLocation

public RowLocation getRowLocation()
                           throws StandardException

Description copied from interface: CursorResultSet

Returns the row location of the current base table row of the cursor. If this cursor's row is composed of multiple base tables' rows, i.e. due to a join, then a null is returned.

Specified by:

getRowLocation in interface CursorResultSet

Returns:

the row location of the current cursor row.

Throws:

StandardException - thrown on failure

See Also:

CursorResultSet

getOpType

public int getOpType()

Return the set operation of this SetOpResultSet

Returns:

the set operation of this ResultSet, the value is either IntersectOrExceptNode.INTERSECT_OP for Intersect operation or IntersectOrExceptNode.EXCEPT_OP for Except operation

See Also:

IntersectOrExceptNode

getResultSetNumber

public int getResultSetNumber()

Return the result set number

Returns:

the result set number

getLeftSourceInput

public NoPutResultSet getLeftSourceInput()

Return the left source input of this SetOpResultSet

Returns:

the left source input of this SetOpResultSet

See Also:

NoPutResultSet

getRightSourceInput

public NoPutResultSet getRightSourceInput()

Return the right source input of this SetOpResultSet

Returns:

the right source input of this SetOpResultSet

See Also:

NoPutResultSet

getRowsSeenLeft

public int getRowsSeenLeft()

Return the number of rows seen on the left source input

Returns:

the number of rows seen on the left source input

getRowsSeenRight

public int getRowsSeenRight()

Return the number of rows seen on the right source input

Returns:

the number of rows seen on the right source input

getRowsReturned

public int getRowsReturned()

Return the number of rows returned from the result set

Returns:

the number of rows returned from the result set