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

java.lang.Object
  org.apache.derby.impl.sql.execute.BasicNoPutResultSetImpl
      org.apache.derby.impl.sql.execute.NoPutResultSetImpl
          org.apache.derby.impl.sql.execute.ProjectRestrictResultSet

All Implemented Interfaces:

CursorResultSet, NoPutResultSet, ResultSet, RowLocationRetRowSource, RowSource

 class ProjectRestrictResultSet
extends NoPutResultSetImpl
implements CursorResultSet

Takes a table and a table filter and returns the table's rows satisfying the filter as a result set.

Field Summary

private boolean[]	cloneMap Holds columns present more than once in the result set and which may be represented by a stream, since such columns need to be cloned.
GeneratedMethod	constantRestriction
boolean	doesProjection
private ExecRow	mappedResultRow
private GeneratedMethod	projection
long	projectionTime
private int[]	projectMapping
private ExecRow	projRow
GeneratedMethod	restriction
long	restrictionTime
boolean	reuseResult
private boolean	runTimeStatsOn
private boolean	shortCircuitOpen
(package private) NoPutResultSet	source

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

checkNullCols, clonedExecRow, cncLen, resultSetNumber, targetResultSet

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

activation, 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

ProjectRestrictResultSet(NoPutResultSet s, Activation a, GeneratedMethod r, GeneratedMethod p, int resultSetNumber, GeneratedMethod cr, int mapRefItem, int cloneMapItem, boolean reuseResult, boolean doesProjection, double optimizerEstimatedRowCount, double optimizerEstimatedCost)

Method Summary

void	close() If the result set has been opened, close the open scan.
ExecRow	doBaseRowProjection(ExecRow sourceRow) Do the projection against the sourceRow.
private ExecRow	doProjection(ExecRow sourceRow) Do the projection against the source row.
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().
int[]	getBaseProjectMapping() Get projection mapping array.
ExecRow	getCurrentRow() Gets last row returned.
ExecRow	getNextRowCore() Return the requested values computed from the next row (if any) for which the restriction evaluates to true.
RowLocation	getRowLocation() Gets information from its source.
long	getTimeSpent(int type) Return the total amount of time spent in this ResultSet
boolean	isForUpdate() Is this ResultSet or it's source result set for update
void	markRowAsDeleted() Marks the resultSet's currentRow as deleted after a delete has been issued by either by using positioned delete or JDBC's deleteRow method.
void	openCore() open a scan on the table. scan parameters are evaluated at each open, so there is probably some way of altering their values...
void	reopenCore() reopen a scan on the table. scan parameters are evaluated at each open, so there is probably some way of altering their values...
void	updateRow(ExecRow row, RowChanger rowChanger) Updates the resultSet's current row with it's new values after an update has been issued either using positioned update or JDBC's udpateRow method.

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

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

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, markAsTopResultSet, modifiedRowCount, open, recordConstructorTime, 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

restrictionTime

public long restrictionTime

projectionTime

public long projectionTime

source

final NoPutResultSet source

constantRestriction

public GeneratedMethod constantRestriction

restriction

public GeneratedMethod restriction

doesProjection

public boolean doesProjection

projection

private GeneratedMethod projection

projectMapping

private int[] projectMapping

cloneMap

private boolean[] cloneMap

Holds columns present more than once in the result set and which may be represented by a stream, since such columns need to be cloned.

runTimeStatsOn

private boolean runTimeStatsOn

mappedResultRow

private ExecRow mappedResultRow

reuseResult

public boolean reuseResult

shortCircuitOpen

private boolean shortCircuitOpen

projRow

private ExecRow projRow

Constructor Detail

ProjectRestrictResultSet

ProjectRestrictResultSet(NoPutResultSet s,
                         Activation a,
                         GeneratedMethod r,
                         GeneratedMethod p,
                         int resultSetNumber,
                         GeneratedMethod cr,
                         int mapRefItem,
                         int cloneMapItem,
                         boolean reuseResult,
                         boolean doesProjection,
                         double optimizerEstimatedRowCount,
                         double optimizerEstimatedCost)
                   throws StandardException

Throws:

StandardException

Method Detail

openCore

public void openCore()
              throws StandardException

open a scan on the table. scan parameters are evaluated at each open, so there is probably some way of altering their values...

Specified by:

openCore in interface NoPutResultSet

Throws:

StandardException - thrown if cursor finished.

reopenCore

public void reopenCore()
                throws StandardException

reopen a scan on the table. scan parameters are evaluated at each open, so there is probably some way of altering their values...

Specified by:

reopenCore in interface NoPutResultSet

Overrides:

reopenCore in class BasicNoPutResultSetImpl

Throws:

StandardException - thrown if cursor finished.

See Also:

NoPutResultSet.openCore()

getNextRowCore

public ExecRow getNextRowCore()
                       throws StandardException

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 in the result

Throws:

StandardException - thrown on failure.

StandardException - ResultSetNotOpen thrown if not yet open.

See Also:

NoPutResultSet.getNextRowCore()

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).

close

public void close()
           throws StandardException

If the result set has been opened, close the open scan.

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

getRowLocation

public RowLocation getRowLocation()
                           throws StandardException

Gets information from its source. We might want to have this take a CursorResultSet in its constructor some day, instead of doing a cast here?

Specified by:

getRowLocation in interface CursorResultSet

Returns:

the row location of the current cursor row.

Throws:

StandardException - thrown on failure.

See Also:

CursorResultSet

getCurrentRow

public ExecRow getCurrentRow()
                      throws StandardException

Gets last row returned.

Specified by:

getCurrentRow in interface CursorResultSet

Returns:

the last row returned.

Throws:

StandardException - thrown on failure.

See Also:

CursorResultSet

doProjection

private ExecRow doProjection(ExecRow sourceRow)
                      throws StandardException

Do the projection against the source row. Use reflection where necessary, otherwise get the source column into our result row.

Parameters:

sourceRow - The source row.

Returns:

The result of the projection

Throws:

StandardException - thrown on failure.

doBaseRowProjection

public ExecRow doBaseRowProjection(ExecRow sourceRow)
                            throws StandardException

Do the projection against the sourceRow. If the source of the result set is of type ProjectRestrictResultSet, the projection by that result set will also be performed.

Parameters:

sourceRow - row to be projected

Returns:

The result of the projection

Throws:

StandardException - thrown on failure.

getBaseProjectMapping

public int[] getBaseProjectMapping()

Get projection mapping array. The array consist of indexes which maps the column in a row array to another position in the row array. If the value is projected out of the row, the value is negative.

Returns:

projection mapping array.

isForUpdate

public boolean isForUpdate()

Is this ResultSet or it's source result set for update

Specified by:

isForUpdate in interface NoPutResultSet

Overrides:

isForUpdate in class NoPutResultSetImpl

Returns:

Whether or not the result set is for update.

updateRow

public void updateRow(ExecRow row,
                      RowChanger rowChanger)
               throws StandardException

Description copied from interface: NoPutResultSet

Updates the resultSet's current row with it's new values after an update has been issued either using positioned update or JDBC's udpateRow method.

Specified by:

updateRow in interface NoPutResultSet

Overrides:

updateRow in class NoPutResultSetImpl

Parameters:

row - new values for the currentRow

rowChanger - holds information about row: what columns of it is to be used for updating, and what underlying base table column each such column corresponds to.

Throws:

StandardException - thrown on failure.

See Also:

NoPutResultSet.updateRow(org.apache.derby.iapi.sql.execute.ExecRow, org.apache.derby.iapi.sql.execute.RowChanger)

markRowAsDeleted

public void markRowAsDeleted()
                      throws StandardException

Description copied from interface: NoPutResultSet

Marks the resultSet's currentRow as deleted after a delete has been issued by either by using positioned delete or JDBC's deleteRow method.

Specified by:

markRowAsDeleted in interface NoPutResultSet

Overrides:

markRowAsDeleted in class NoPutResultSetImpl

Throws:

StandardException - thrown on failure.

See Also:

NoPutResultSet.markRowAsDeleted()