Package org.h2.expression.analysis

Class WindowFrameBound

java.lang.Object

org.h2.expression.analysis.WindowFrameBound

public class WindowFrameBound
extends java.lang.Object

Window frame bound.

Field Summary

Fields

Modifier and Type	Field	Description
private int	expressionIndex
private boolean	isVariable
private WindowFrameBoundType	type
private Expression	value

Constructor Summary

Constructors

Constructor	Description
WindowFrameBound(WindowFrameBoundType type, Expression value)	Creates new instance of window frame bound.

Method Summary

Modifier and Type	Method	Description
int	getExpressionIndex()	Returns the index of preserved expression.
java.lang.StringBuilder	getSQL(java.lang.StringBuilder builder, boolean following, int sqlFlags)	Appends SQL representation to the specified builder.
WindowFrameBoundType	getType()	Returns the type
Expression	getValue()	Returns the value.
boolean	isParameterized()	Returns whether bound is defined as n PRECEDING or n FOLLOWING.
boolean	isVariable()	Returns whether bound is defined with a variable.
(package private) void	mapColumns(ColumnResolver resolver, int level, int state)	Map the columns of the resolver to expression columns.
(package private) void	optimize(SessionLocal session)	Try to optimize bound expression.
(package private) void	setExpressionIndex(int expressionIndex)	Sets the index of preserved expression.
(package private) void	updateAggregate(SessionLocal session, int stage)	Update an aggregate value.

Methods inherited from class java.lang.Object

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

Field Detail

type

private final WindowFrameBoundType type

value

private Expression value

isVariable

private boolean isVariable

expressionIndex

private int expressionIndex

Constructor Detail

WindowFrameBound

public WindowFrameBound(WindowFrameBoundType type,
                        Expression value)

Creates new instance of window frame bound.

Parameters:

type - bound type

value - bound value, if any

Method Detail

getType

public WindowFrameBoundType getType()

Returns the type

Returns:

the type

getValue

public Expression getValue()

Returns the value.

Returns:

the value

isParameterized

public boolean isParameterized()

Returns whether bound is defined as n PRECEDING or n FOLLOWING.

Returns:

whether bound is defined as n PRECEDING or n FOLLOWING

isVariable

public boolean isVariable()

Returns whether bound is defined with a variable. This method may be used only after optimize(SessionLocal) invocation.

Returns:

whether bound is defined with a variable

getExpressionIndex

public int getExpressionIndex()

Returns the index of preserved expression.

Returns:

the index of preserved expression, or -1

setExpressionIndex

void setExpressionIndex(int expressionIndex)

Sets the index of preserved expression.

Parameters:

expressionIndex - the index to set

mapColumns

void mapColumns(ColumnResolver resolver,
                int level,
                int state)

Map the columns of the resolver to expression columns.

Parameters:

resolver - the column resolver

level - the subquery nesting level

state - current state for nesting checks

optimize

void optimize(SessionLocal session)

Try to optimize bound expression.

Parameters:

session - the session

updateAggregate

void updateAggregate(SessionLocal session,
                     int stage)

Update an aggregate value.

Parameters:

session - the session

stage - select stage

See Also:

Expression.updateAggregate(SessionLocal, int)

getSQL

public java.lang.StringBuilder getSQL(java.lang.StringBuilder builder,
                                      boolean following,
                                      int sqlFlags)

Appends SQL representation to the specified builder.

Parameters:

builder - string builder

following - if false return SQL for starting clause, if true return SQL for following clause

sqlFlags - formatting flags

Returns:

the specified string builder

See Also:

Expression.getSQL(StringBuilder, int, int)