NoRowsResultSetImpl (Apache Derby V10.14 Internals)

java.lang.Object
- org.apache.derby.impl.sql.execute.NoRowsResultSetImpl

All Implemented Interfaces:

ResultSet

Direct Known Subclasses:

CallStatementResultSet, DMLWriteResultSet, MergeResultSet, MiscResultSet
```
abstract class NoRowsResultSetImpl
extends java.lang.Object
implements ResultSet
```
Abstract ResultSet for implementations that do not return rows. Examples are DDL statements, CALL statements and DML.
An implementation must provide a ResultSet.open() method that performs the required action.
ResultSet.returnsRows() returns false and any method that fetches a row will throw an exception.

Field Summary

Fields
Modifier and Type	Field	Description
`(package private) Activation`	`activation`
`protected long`	`beginExecutionTime`
`protected long`	`beginTime`
`protected long`	`endExecutionTime`
`protected long`	`endTime`
`private int`	`firstColumn`
`private int[]`	`generatedColumnPositions`
`private boolean`	`isOpen`	True if the result set has been opened, and not yet closed.
`(package private) LanguageConnectionContext`	`lcc`
`private DataValueDescriptor[]`	`normalizedGeneratedValues`
`private boolean`	`statisticsTimingOn`
`private NoPutResultSet[]`	`subqueryTrackingArray`

Fields inherited from interface org.apache.derby.iapi.sql.ResultSet
CURRENT_RESULTSET_ONLY, ENTIRE_RESULTSET_TREE, ISAFTERLAST, ISBEFOREFIRST, ISFIRST, ISLAST

Constructor Summary

Constructors
Constructor Description

NoRowsResultSetImpl(Activation activation)

Constructors
Constructor	Description
`NoRowsResultSetImpl(Activation activation)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`addWarning(java.sql.SQLWarning w)`	Add a warning to this result set.
`boolean`	`checkRowPosition(int isType)`	Determine if the cursor is before the first row in the result set.
`void`	`clearCurrentRow()`	Clear the current row.
`void`	`close(boolean underMerge)`	Dump the stat if not already done so.
`boolean`	`doesCommit()`	Does this ResultSet cause a commit or rollback.
`void`	`evaluateGenerationClauses(GeneratedMethod generationClauses, Activation activation, NoPutResultSet source, ExecRow newRow, boolean isUpdate)`	Compute the generation clauses on the current row in order to fill in computed columns.
`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`	`getAbsoluteRow(int row)`	Returns the row at the absolute position from the query, and returns NULL when there is no such position.
`Activation`	`getActivation()`
`ResultSet`	`getAutoGeneratedKeysResultset()`	ResultSet for rows inserted into the table (contains auto-generated keys columns only)
`java.sql.Timestamp`	`getBeginExecutionTimestamp()`	Get the Timestamp for the beginning of execution.
`protected long`	`getCurrentTimeMillis()`	Return the current time in milliseconds, if DEBUG and RunTimeStats is on, else return 0.
`java.lang.String`	`getCursorName()`	Return the cursor name, null in this case.
`java.sql.Timestamp`	`getEndExecutionTimestamp()`	Get the Timestamp for the end of execution.
`long`	`getExecuteTime()`	Get the execution time in milliseconds.
`ExecRow`	`getFirstRow()`	Returns the first row from the query, and returns NULL when there are no rows.
`ExecRow`	`getLastRow()`	Returns the last row from the query, and returns NULL when there are no rows.
`ExecRow`	`getNextRow()`	No rows to return, so throw an exception.
`ExecRow`	`getPreviousRow()`	Returns the previous row from the query, and returns NULL when there are no more previous rows.
`java.lang.String`	`getQueryPlanText(int depth)`	RESOLVE - This method will go away once it is overloaded in all subclasses.
`ExecRow`	`getRelativeRow(int row)`	Returns the row at the relative position from the current cursor position, and returns NULL when there is no such position.
`ResultDescription`	`getResultDescription()`	Returns null.
`int`	`getRowNumber()`	Returns the row number of the current row.
`NoPutResultSet[]`	`getSubqueryTrackingArray(int numSubqueries)`	Get the subquery ResultSet tracking array from the top ResultSet.
`long`	`getTimeSpent(int type)`	Return the total amount of time spent in this ResultSet
`java.sql.SQLWarning`	`getWarnings()`	Return the set of warnings generated during the execution of this result set.
`boolean`	`isClosed()`	Find out if the `ResultSet` is closed.
`long`	`modifiedRowCount()`	Returns zero.
`boolean`	`returnsRows()`	Returns FALSE
`ExecRow`	`setAfterLastRow()`	Sets the current position to after the last row and returns NULL because there is no current row.
`ExecRow`	`setBeforeFirstRow()`	Sets the current position to before the first row and returns NULL because there is no current row.
`(package private) void`	`setup()`	Set up the result set for use.
`private void`	`setupGeneratedColumns(Activation activation, ValueRow newRow)`	Construct support for normalizing generated columns.
`org.w3c.dom.Element`	`toXML(org.w3c.dom.Element parentNode, java.lang.String tag)`	Produce an xml image of this ResultSet and its descendant ResultSets.

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
cleanUp, close, open

- Field Detail
  - activation
```
final Activation activation
```
  - subqueryTrackingArray
```
private NoPutResultSet[] subqueryTrackingArray
```
  - statisticsTimingOn
```
private final boolean statisticsTimingOn
```
  - isOpen
```
private boolean isOpen
```
    True if the result set has been opened, and not yet closed.
  - lcc
```
final LanguageConnectionContext lcc
```
  - beginTime
```
protected long beginTime
```
  - endTime
```
protected long endTime
```
  - beginExecutionTime
```
protected long beginExecutionTime
```
  - endExecutionTime
```
protected long endExecutionTime
```
  - firstColumn
```
private int firstColumn
```
  - generatedColumnPositions
```
private int[] generatedColumnPositions
```
  - normalizedGeneratedValues
```
private DataValueDescriptor[] normalizedGeneratedValues
```
- Constructor Detail
  - NoRowsResultSetImpl
```
NoRowsResultSetImpl(Activation activation)
```
- Method Detail
  - setup
```
void setup()
    throws StandardException
```
    Set up the result set for use. Should always be called from open().
    
    Throws:
    
    StandardException - thrown on error
  - returnsRows
```
public final boolean returnsRows()
```
    Returns FALSE
    
    Specified by:
    
    returnsRows in interface ResultSet
    
    Returns:
    
    TRUE if the statement returns rows, FALSE if not.
  - modifiedRowCount
```
public long modifiedRowCount()
```
    Returns zero.
    
    Specified by:
    
    modifiedRowCount in interface ResultSet
    
    Returns:
    
    The number of rows affect by the statement, so far.
  - getResultDescription
```
public ResultDescription getResultDescription()
```
    Returns null.
    
    Specified by:
    
    getResultDescription in interface ResultSet
    
    Returns:
    
    A ResultDescription describing the results of the statement.
  - getActivation
```
public final Activation getActivation()
```
    Specified by:
    
    getActivation in interface ResultSet
  - getAbsoluteRow
```
public final ExecRow getAbsoluteRow(int row)
                             throws StandardException
```
    Returns the row at the absolute position from the query, and returns NULL when there is no such position. (Negative position means from the end of the result set.) Moving the cursor to an invalid position leaves the cursor positioned either before the first row (negative position) or after the last row (positive position). NOTE: An exception will be thrown on 0.
    
    Specified by:
    
    getAbsoluteRow in interface ResultSet
    
    Parameters:
    
    row - The position.
    
    Returns:
    
    The row at the absolute position, or NULL if no such position.
    
    Throws:
    
    StandardException - Thrown on failure
    
    See Also:
    
    Row
  - getRelativeRow
```
public final ExecRow getRelativeRow(int row)
                             throws StandardException
```
    Returns the row at the relative position from the current cursor position, and returns NULL when there is no such position. (Negative position means toward the beginning of the result set.) Moving the cursor to an invalid position leaves the cursor positioned either before the first row (negative position) or after the last row (positive position). NOTE: 0 is valid. NOTE: An exception is thrown if the cursor is not currently positioned on a row.
    
    Specified by:
    
    getRelativeRow in interface ResultSet
    
    Parameters:
    
    row - The position.
    
    Returns:
    
    The row at the relative position, or NULL if no such position.
    
    Throws:
    
    StandardException - Thrown on failure
    
    See Also:
    
    Row
  - setBeforeFirstRow
```
public final ExecRow setBeforeFirstRow()
                                throws StandardException
```
    Sets the current position to before the first row and returns NULL because there is no current row.
    
    Specified by:
    
    setBeforeFirstRow in interface ResultSet
    
    Returns:
    
    NULL.
    
    Throws:
    
    StandardException - Thrown on failure
    
    See Also:
    
    Row
  - getFirstRow
```
public final ExecRow getFirstRow()
                          throws StandardException
```
    Returns the first row from the query, and returns NULL when there are no rows.
    
    Specified by:
    
    getFirstRow in interface ResultSet
    
    Returns:
    
    The first row, or NULL if no rows.
    
    Throws:
    
    StandardException - Thrown on failure
    
    See Also:
    
    Row
  - getNextRow
```
public final ExecRow getNextRow()
                         throws StandardException
```
    No rows to return, so throw an exception.
    
    Specified by:
    
    getNextRow in interface ResultSet
    
    Returns:
    
    The next row, or NULL if no more rows.
    
    Throws:
    
    StandardException - Always throws a StandardException to indicate that this method is not intended to be used.
    
    See Also:
    
    Row
  - getPreviousRow
```
public final ExecRow getPreviousRow()
                             throws StandardException
```
    Returns the previous row from the query, and returns NULL when there are no more previous rows.
    
    Specified by:
    
    getPreviousRow in interface ResultSet
    
    Returns:
    
    The previous row, or NULL if no more previous rows.
    
    Throws:
    
    StandardException - Thrown on failure
    
    See Also:
    
    Row
  - getLastRow
```
public final ExecRow getLastRow()
                         throws StandardException
```
    Returns the last row from the query, and returns NULL when there are no rows.
    
    Specified by:
    
    getLastRow in interface ResultSet
    
    Returns:
    
    The last row, or NULL if no rows.
    
    Throws:
    
    StandardException - Thrown on failure
    
    See Also:
    
    Row
  - setAfterLastRow
```
public final ExecRow setAfterLastRow()
                              throws StandardException
```
    Sets the current position to after the last row and returns NULL because there is no current row.
    
    Specified by:
    
    setAfterLastRow in interface ResultSet
    
    Returns:
    
    NULL.
    
    Throws:
    
    StandardException - Thrown on failure
    
    See Also:
    
    Row
  - clearCurrentRow
```
public final void clearCurrentRow()
```
    Clear the current row. This is done after a commit on holdable result sets. This is a no-op on result set which do not provide rows.
    
    Specified by:
    
    clearCurrentRow in interface ResultSet
  - checkRowPosition
```
public final boolean checkRowPosition(int isType)
```
    Determine if the cursor is before the first row in the result set.
    
    Specified by:
    
    checkRowPosition in interface ResultSet
    
    Returns:
    
    true if before the first row, false otherwise. Returns false when the result set contains no rows.
  - getRowNumber
```
public final int getRowNumber()
```
    Returns the row number of the current row. Row numbers start from 1 and go to 'n'. Corresponds to row numbering used to position current row in the result set (as per JDBC).
    
    Specified by:
    
    getRowNumber in interface ResultSet
    
    Returns:
    
    the row number, or 0 if not on a row
  - close
```
public void close(boolean underMerge)
           throws StandardException
```
    Dump the stat if not already done so. Close all of the open subqueries.
    
    Parameters:
    
    underMerge - True if this is part of an action of a MERGE statement.
    
    Throws:
    
    StandardException - thrown on error
  - isClosed
```
public boolean isClosed()
```
    Find out if the ResultSet is closed.
    
    Specified by:
    
    isClosed in interface ResultSet
    
    Returns:
    
    true if closed, false otherwise
  - 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
    
    Throws:
    
    StandardException - on error
  - getExecuteTime
```
public long getExecuteTime()
```
    Get the execution time in milliseconds.
    
    Specified by:
    
    getExecuteTime in interface ResultSet
    
    Returns:
    
    long The execution time in milliseconds.
  - getBeginExecutionTimestamp
```
public java.sql.Timestamp getBeginExecutionTimestamp()
```
    Get the Timestamp for the beginning of execution.
    
    Specified by:
    
    getBeginExecutionTimestamp in interface ResultSet
    
    Returns:
    
    Timestamp The Timestamp for the beginning of execution.
  - getEndExecutionTimestamp
```
public java.sql.Timestamp getEndExecutionTimestamp()
```
    Get the Timestamp for the end of execution.
    
    Specified by:
    
    getEndExecutionTimestamp in interface ResultSet
    
    Returns:
    
    Timestamp The Timestamp for the end of execution.
  - getQueryPlanText
```
public java.lang.String getQueryPlanText(int depth)
```
    RESOLVE - This method will go away once it is overloaded in all subclasses. Return the query plan as a String.
    
    Parameters:
    
    depth - Indentation level.
    
    Returns:
    
    String The query plan as a String.
  - 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).
  - getSubqueryTrackingArray
```
public final NoPutResultSet[] getSubqueryTrackingArray(int numSubqueries)
```
    Description copied from interface: ResultSet
    
    Get the subquery ResultSet tracking array from the top ResultSet. (Used for tracking open subqueries when closing down on an error.)
    
    Specified by:
    
    getSubqueryTrackingArray in interface ResultSet
    
    Parameters:
    
    numSubqueries - The size of the array (For allocation on demand.)
    
    Returns:
    
    NoPutResultSet[] Array of NoPutResultSets for subqueries.
    
    See Also:
    
    ResultSet.getSubqueryTrackingArray(int)
  - getAutoGeneratedKeysResultset
```
public ResultSet getAutoGeneratedKeysResultset()
```
    Description copied from interface: ResultSet
    
    ResultSet for rows inserted into the table (contains auto-generated keys columns only)
    
    Specified by:
    
    getAutoGeneratedKeysResultset in interface ResultSet
    
    Returns:
    
    NoPutResultSet NoPutResultSets for rows inserted into the table.
    
    See Also:
    
    ResultSet.getAutoGeneratedKeysResultset()
  - getCursorName
```
public java.lang.String getCursorName()
```
    Return the cursor name, null in this case.
    
    Specified by:
    
    getCursorName in interface ResultSet
    
    Returns:
    
    A String with the name of the cursor, if any. Returns NULL if this is not a cursor statement.
    
    See Also:
    
    ResultSet.getCursorName()
  - getCurrentTimeMillis
```
protected final long getCurrentTimeMillis()
```
    Return the current time in milliseconds, if DEBUG and RunTimeStats is on, else return 0. (Only pay price of system call if need to.)
    
    Returns:
    
    long Current time in milliseconds.
  - evaluateGenerationClauses
```
public void evaluateGenerationClauses(GeneratedMethod generationClauses,
                                      Activation activation,
                                      NoPutResultSet source,
                                      ExecRow newRow,
                                      boolean isUpdate)
                               throws StandardException
```
    Compute the generation clauses on the current row in order to fill in computed columns.
    
    Parameters:
    
    generationClauses - the generated method which evaluates generation clauses
    
    activation - the thread-specific instance of the generated class
    
    source - the tuple stream driving this INSERT/UPDATE
    
    newRow - the base row being stuffed
    
    isUpdate - true if this is an UPDATE. false otherwise.
    
    Throws:
    
    StandardException
  - setupGeneratedColumns
```
private void setupGeneratedColumns(Activation activation,
                                   ValueRow newRow)
                            throws StandardException
```
    Construct support for normalizing generated columns. This figures out which columns in the target row have generation clauses which need to be run.
    
    Throws:
    
    StandardException
  - doesCommit
```
public boolean doesCommit()
```
    Does this ResultSet cause a commit or rollback.
    
    Returns:
    
    Whether or not this ResultSet cause a commit or rollback.
  - addWarning
```
public void addWarning(java.sql.SQLWarning w)
```
    Description copied from interface: ResultSet
    
    Add a warning to this result set.
    
    Specified by:
    
    addWarning in interface ResultSet
    
    Parameters:
    
    w - the warning to add
  - getWarnings
```
public java.sql.SQLWarning getWarnings()
```
    Description copied from interface: ResultSet
    
    Return the set of warnings generated during the execution of this result set. The warnings are cleared once this call returns.
    
    Specified by:
    
    getWarnings in interface ResultSet
  - toXML
```
public org.w3c.dom.Element toXML(org.w3c.dom.Element parentNode,
                                 java.lang.String tag)
                          throws java.lang.Exception
```
    Description copied from interface: ResultSet
    
    Produce an xml image of this ResultSet and its descendant ResultSets. Appends an element to the parentNode and returns the appended element.
    
    Specified by:
    
    toXML in interface ResultSet
    
    Parameters:
    
    parentNode - Node to put content into.
    
    tag - Element tag for content
    
    Returns:
    
    the content as an element with the given tag name
    
    Throws:
    
    java.lang.Exception

Class NoRowsResultSetImpl

Field Summary

Fields inherited from interface org.apache.derby.iapi.sql.ResultSet

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.derby.iapi.sql.ResultSet

Field Detail

activation

subqueryTrackingArray

statisticsTimingOn

isOpen

lcc

beginTime

endTime

beginExecutionTime

endExecutionTime

firstColumn

generatedColumnPositions

normalizedGeneratedValues

Constructor Detail

NoRowsResultSetImpl

Method Detail

setup

returnsRows

modifiedRowCount

getResultDescription

getActivation

getAbsoluteRow

getRelativeRow

setBeforeFirstRow

getFirstRow

getNextRow

getPreviousRow

getLastRow

setAfterLastRow

clearCurrentRow

checkRowPosition

getRowNumber

close

isClosed

finish

getExecuteTime

getBeginExecutionTimestamp

getEndExecutionTimestamp

getQueryPlanText

getTimeSpent

getSubqueryTrackingArray

getAutoGeneratedKeysResultset

getCursorName

getCurrentTimeMillis

evaluateGenerationClauses

setupGeneratedColumns

doesCommit

addWarning

getWarnings

toXML