org.apache.derby.impl.sql.execute

Class NormalizeResultSet

java.lang.Object

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

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

org.apache.derby.impl.sql.execute.NormalizeResultSet

All Implemented Interfaces:

CursorResultSet, NoPutResultSet, ResultSet, RowLocationRetRowSource, RowSource

class NormalizeResultSet
extends NoPutResultSetImpl
implements CursorResultSet

Cast the rows from the source result set to match the format of the result set for the entire statement.

Field Summary

Fields

Modifier and Type	Field and Description
private DataValueDescriptor[]	cachedDestinations This array contains data value descriptors that can be used (and reused) by normalizeRow() to hold the normalized column values.
private DataTypeDescriptor[]	desiredTypes
private ExecRow	normalizedRow
private int	numCols
private ResultDescription	resultDescription
NoPutResultSet	source
private int	startCol

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, 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
NormalizeResultSet(NoPutResultSet source, Activation activation, int resultSetNumber, int erdNumber, double optimizerEstimatedRowCount, double optimizerEstimatedCost, boolean forUpdate) Constructor for a NormalizeResultSet

Method Summary

Modifier and Type	Method and Description
void	close() If the result set has been opened, close the open scan.
static int	computeStartColumn(boolean isUpdate, ResultDescription desc) Compute the start column for an update/insert.
private DataTypeDescriptor[]	fetchResultTypes(ResultDescription desc) Fetch the result datatypes out of the activation.
private DataValueDescriptor	getCachedDestination(int col) Get a cached data value descriptor that can receive the normalized value of the specified column.
ExecRow	getCurrentRow() Gets information from last getNextRow call.
private DataTypeDescriptor	getDesiredType(int col) Get a data type descriptor that describes the desired type for the specified column.
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
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.
static DataValueDescriptor	normalizeColumn(DataTypeDescriptor dtd, ExecRow sourceRow, int sourceColumnPosition, DataValueDescriptor resultCol, ResultDescription desc) Normalize a column.
private ExecRow	normalizeRow(ExecRow sourceRow) Normalize a row.
void	openCore() open a scan on the source. 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, isForUpdate, 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, finish, 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, 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, finish, getAbsoluteRow, getActivation, getAutoGeneratedKeysResultset, getBeginExecutionTimestamp, getCursorName, getEndExecutionTimestamp, getExecuteTime, getFirstRow, getLastRow, getNextRow, getPreviousRow, getRelativeRow, getResultDescription, getRowNumber, getSubqueryTrackingArray, getWarnings, isClosed, modifiedRowCount, open, returnsRows, setAfterLastRow, setBeforeFirstRow

Field Detail

source

public NoPutResultSet source

normalizedRow

private ExecRow normalizedRow

numCols

private int numCols

startCol

private int startCol

cachedDestinations

private final DataValueDescriptor[] cachedDestinations

This array contains data value descriptors that can be used (and reused) by normalizeRow() to hold the normalized column values.

resultDescription

private ResultDescription resultDescription

desiredTypes

private DataTypeDescriptor[] desiredTypes

Constructor Detail

NormalizeResultSet

public NormalizeResultSet(NoPutResultSet source,
                          Activation activation,
                          int resultSetNumber,
                          int erdNumber,
                          double optimizerEstimatedRowCount,
                          double optimizerEstimatedCost,
                          boolean forUpdate)
                   throws StandardException

Constructor for a NormalizeResultSet

Parameters:

source - The NoPutResultSet from which to get rows to be normalized

activation - The activation for this execution

resultSetNumber - The resultSetNumber

erdNumber - The integer for the ResultDescription

Throws:

StandardException - on error

Method Detail

openCore

public void openCore()
              throws StandardException

open a scan on the source. 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 on failure

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

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 in the result

Throws:

StandardException - thrown on failure

See Also:

NoPutResultSet.getNextRowCore()

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

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

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()

Gets information from last getNextRow call.

Specified by:

getCurrentRow in interface CursorResultSet

Returns:

the last row returned.

See Also:

CursorResultSet

computeStartColumn

public static int computeStartColumn(boolean isUpdate,
                                     ResultDescription desc)

Compute the start column for an update/insert.

Parameters:

isUpdate - True if we are executing an UPDATE statement

desc - Metadata describing a result row

normalizeColumn

public static DataValueDescriptor normalizeColumn(DataTypeDescriptor dtd,
                                                  ExecRow sourceRow,
                                                  int sourceColumnPosition,
                                                  DataValueDescriptor resultCol,
                                                  ResultDescription desc)
                                           throws StandardException

Normalize a column. For now, this means calling constructors through the type services to normalize a type to itself. For example, if you're putting a char(30) value into a char(15) column, it calls a SQLChar constructor with the char(30) value, and the constructor truncates the value and makes sure that no non-blank characters are truncated.

Parameters:

dtd - Data type to coerce to

sourceRow - row holding the source column

sourceColumnPosition - position of column in row

resultCol - where to stuff the coerced value

desc - Additional metadata for error reporting if necessary

Throws:

StandardException - thrown on failure

normalizeRow

private ExecRow normalizeRow(ExecRow sourceRow)
                      throws StandardException

Normalize a row.

Parameters:

sourceRow - The row to normalize

Returns:

The normalized row

Throws:

StandardException - thrown on failure

getCachedDestination

private DataValueDescriptor getCachedDestination(int col)
                                          throws StandardException

Get a cached data value descriptor that can receive the normalized value of the specified column.

Parameters:

col - the column number (1-based)

Returns:

a data value descriptor of the correct type for the column

Throws:

StandardException - if a new data value descriptor cannot be created

getDesiredType

private DataTypeDescriptor getDesiredType(int col)

Get a data type descriptor that describes the desired type for the specified column.

Parameters:

col - the column number (1-based)

Returns:

a data type descriptor for the column

fetchResultTypes

private DataTypeDescriptor[] fetchResultTypes(ResultDescription desc)

Fetch the result datatypes out of the activation.

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()