org.h2.expression.analysis

Class WindowFrame

java.lang.Object

org.h2.expression.analysis.WindowFrame

public final class WindowFrame
extends java.lang.Object

Window frame clause.

Constructor Summary

Constructors

Constructor and Description
WindowFrame(WindowFrameUnits units, WindowFrameBound starting, WindowFrameBound following, WindowFrameExclusion exclusion) Creates new instance of window frame clause.

Method Summary

Methods

Modifier and Type	Method and Description
static int	getEndIndex(Window over, Session session, java.util.ArrayList<Value[]> orderedRows, SortOrder sortOrder, int currentRow) Returns end index for the specified frame, or default end index if frame is null.
WindowFrameExclusion	getExclusion() Returns the exclusion clause.
WindowFrameBound	getFollowing() Returns the following clause.
java.lang.StringBuilder	getSQL(java.lang.StringBuilder builder) Append SQL representation to the specified builder.
int	getStartIndex(Session session, java.util.ArrayList<Value[]> orderedRows, SortOrder sortOrder, int currentRow) Returns start index of this frame,
WindowFrameBound	getStarting() Returns the starting clause.
WindowFrameUnits	getUnits() Returns the units.
boolean	isValid() Checks validity of this frame.
boolean	isVariableBounds() Check if bounds of this frame has variable expressions.
java.util.Iterator<Value[]>	iterator(Session session, java.util.ArrayList<Value[]> orderedRows, SortOrder sortOrder, int currentRow, boolean reverse) Returns iterator.
static java.util.Iterator<Value[]>	iterator(Window over, Session session, java.util.ArrayList<Value[]> orderedRows, SortOrder sortOrder, int currentRow, boolean reverse) Returns iterator for the specified frame, or default iterator if frame is null.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

WindowFrame

public WindowFrame(WindowFrameUnits units,
           WindowFrameBound starting,
           WindowFrameBound following,
           WindowFrameExclusion exclusion)

Creates new instance of window frame clause.

Parameters:

units - units

starting - starting clause

following - following clause

exclusion - exclusion clause

Method Detail

iterator

public static java.util.Iterator<Value[]> iterator(Window over,
                                   Session session,
                                   java.util.ArrayList<Value[]> orderedRows,
                                   SortOrder sortOrder,
                                   int currentRow,
                                   boolean reverse)

Returns iterator for the specified frame, or default iterator if frame is null.

Parameters:

over - window

session - the session

orderedRows - ordered rows

sortOrder - sort order

currentRow - index of the current row

reverse - whether iterator should iterate in reverse order

Returns:

iterator

getEndIndex

public static int getEndIndex(Window over,
              Session session,
              java.util.ArrayList<Value[]> orderedRows,
              SortOrder sortOrder,
              int currentRow)

Returns end index for the specified frame, or default end index if frame is null.

Parameters:

over - window

session - the session

orderedRows - ordered rows

sortOrder - sort order

currentRow - index of the current row

Returns:

end index

Throws:

java.lang.UnsupportedOperationException - if over is not null and its exclusion clause is not EXCLUDE NO OTHERS

getUnits

public WindowFrameUnits getUnits()

Returns the units.

Returns:

the units

getStarting

public WindowFrameBound getStarting()

Returns the starting clause.

Returns:

the starting clause

getFollowing

public WindowFrameBound getFollowing()

Returns the following clause.

Returns:

the following clause, or null

getExclusion

public WindowFrameExclusion getExclusion()

Returns the exclusion clause.

Returns:

the exclusion clause

isValid

public boolean isValid()

Checks validity of this frame.

Returns:

whether bounds of this frame valid

isVariableBounds

public boolean isVariableBounds()

Check if bounds of this frame has variable expressions. This method may be used only after optimize(Session) invocation.

Returns:

if bounds of this frame has variable expressions

iterator

public java.util.Iterator<Value[]> iterator(Session session,
                                   java.util.ArrayList<Value[]> orderedRows,
                                   SortOrder sortOrder,
                                   int currentRow,
                                   boolean reverse)

Returns iterator.

Parameters:

session - the session

orderedRows - ordered rows

sortOrder - sort order

currentRow - index of the current row

reverse - whether iterator should iterate in reverse order

Returns:

iterator

getStartIndex

public int getStartIndex(Session session,
                java.util.ArrayList<Value[]> orderedRows,
                SortOrder sortOrder,
                int currentRow)

Returns start index of this frame,

Parameters:

session - the session

orderedRows - ordered rows

sortOrder - sort order

currentRow - index of the current row

Returns:

start index

Throws:

java.lang.UnsupportedOperationException - if exclusion clause is not EXCLUDE NO OTHERS

getSQL

public java.lang.StringBuilder getSQL(java.lang.StringBuilder builder)

Append SQL representation to the specified builder.

Parameters:

builder - string builder

Returns:

the specified string builder

See Also:

Expression.getSQL(StringBuilder)