Package org.teiid.query.sql.symbol

Class AggregateSymbol

java.lang.Object

org.teiid.query.sql.symbol.Function

org.teiid.query.sql.symbol.AggregateSymbol

All Implemented Interfaces:

Cloneable, LanguageObject, DerivedExpression, Expression, NamedExpression

public class AggregateSymbol
extends Function
implements DerivedExpression, NamedExpression

An aggregate symbol represents an aggregate function. The * expression is encoded by setting the expression to null. This may ONLY be used with the COUNT function.

The type of an aggregate symbol depends on the function and the type of the underlying expression. The type of a COUNT function is ALWAYS integer. MIN and MAX functions take the type of their contained expression.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AggregateSymbol.Type

Nested classes/interfaces inherited from interface org.teiid.query.sql.LanguageObject

LanguageObject.Util

Field Summary

Fields

Modifier and Type	Field	Description
static boolean	LONG_RANKS

Fields inherited from class org.teiid.query.sql.symbol.Function

type

Constructor Summary

Constructors

Modifier	Constructor	Description
	AggregateSymbol(String aggregateFunction, boolean isDistinct, Expression expression)	Construct an aggregate symbol with all given data.
	AggregateSymbol(String aggregateFunction, boolean isDistinct, Expression[] args, OrderBy orderBy)
protected	AggregateSymbol(String name, AggregateSymbol.Type aggregateFunction, boolean isDistinct, Expression[] args)	Constructor used for cloning

Method Summary

Modifier and Type	Method	Description
void	acceptVisitor(LanguageVisitor visitor)	Method for accepting a visitor.
static boolean	areAggregatesCardinalityDependent(Collection<AggregateSymbol> aggs)
boolean	canStage()
Object	clone()	Return a deep copy of this object
boolean	equals(Object obj)	Compare for equality
AggregateSymbol.Type	getAggregateFunction()	Get the aggregate function type - this will map to one of the reserved words for the aggregate functions.
Expression	getCondition()
OrderBy	getOrderBy()
Class<?>	getType()	Get the type of the symbol, which depends on the aggregate function and the type of the contained expression
int	hashCode()	Compute hash code for the object - based on name and hashcode of first arg (if there is one)
boolean	isAnalytical()
boolean	isBoolean()
boolean	isCardinalityDependent()
boolean	isCount()
boolean	isDistinct()	Get the distinct flag.
boolean	isEnhancedNumeric()
boolean	isRanking()
boolean	isRowValueFunction()
boolean	isWindowed()
boolean	respectsNulls()
void	setAggregateFunction(AggregateSymbol.Type aggregateFunction)	Set the aggregate function.
void	setCondition(Expression condition)
void	setDistinct(boolean distinct)
void	setOrderBy(OrderBy orderBy)
void	setWindowed(boolean isWindowed)

Methods inherited from class org.teiid.query.sql.symbol.Function

getArg, getArgs, getFunctionDescriptor, getName, getPushdownFunction, insertConversion, isAggregate, isCalledWithVarArgArrayParam, isEval, isImplicit, makeImplicit, setArgs, setCalledWithVarArgArrayParam, setEval, setFunctionDescriptor, setImplicit, setName, setPushdownFunction, setType, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.teiid.query.sql.symbol.NamedExpression

getName

Field Detail

LONG_RANKS

public static final boolean LONG_RANKS

Constructor Detail

AggregateSymbol

protected AggregateSymbol(String name,
                          AggregateSymbol.Type aggregateFunction,
                          boolean isDistinct,
                          Expression[] args)

Constructor used for cloning

Parameters:

name -

aggregateFunction -

Since:

4.3

AggregateSymbol

public AggregateSymbol(String aggregateFunction,
                       boolean isDistinct,
                       Expression expression)

Construct an aggregate symbol with all given data.

Parameters:

aggregateFunction - Aggregate function type (SQLConstants.NonReserved.COUNT, etc)

isDistinct - True if DISTINCT flag is set

expression - Contained expression

AggregateSymbol

public AggregateSymbol(String aggregateFunction,
                       boolean isDistinct,
                       Expression[] args,
                       OrderBy orderBy)

Method Detail

setAggregateFunction

public void setAggregateFunction(AggregateSymbol.Type aggregateFunction)

Set the aggregate function. If the aggregate function is an invalid value, an IllegalArgumentException is thrown.

Parameters:

aggregateFunction - Aggregate function type

See Also:

SQLConstants.NonReserved.COUNT, SQLConstants.NonReserved.SUM, SQLConstants.NonReserved.AVG, SQLConstants.NonReserved.MIN, SQLConstants.NonReserved.MAX

getAggregateFunction

public AggregateSymbol.Type getAggregateFunction()

Get the aggregate function type - this will map to one of the reserved words for the aggregate functions.

Returns:

Aggregate function type

isRowValueFunction

public boolean isRowValueFunction()

isDistinct

public boolean isDistinct()

Get the distinct flag. If true, aggregate symbol will remove duplicates during computation.

Returns:

True if duplicates should be removed during computation

setDistinct

public void setDistinct(boolean distinct)

getType

public Class<?> getType()

Get the type of the symbol, which depends on the aggregate function and the type of the contained expression

Specified by:

getType in interface Expression

Overrides:

getType in class Function

Returns:

Type of the symbol

isRanking

public boolean isRanking()

isCount

public boolean isCount()

isAnalytical

public boolean isAnalytical()

isBoolean

public boolean isBoolean()

isEnhancedNumeric

public boolean isEnhancedNumeric()

acceptVisitor

public void acceptVisitor(LanguageVisitor visitor)

Description copied from interface: LanguageObject

Method for accepting a visitor. It is the responsibility of the language object to call back on the visitor.

Specified by:

acceptVisitor in interface LanguageObject

Overrides:

acceptVisitor in class Function

Parameters:

visitor - Visitor being used

getOrderBy

public OrderBy getOrderBy()

setOrderBy

public void setOrderBy(OrderBy orderBy)

clone

public Object clone()

Return a deep copy of this object

Specified by:

clone in interface LanguageObject

Overrides:

clone in class Function

Returns:

Deep copy of the object

hashCode

public int hashCode()

Description copied from class: Function

Compute hash code for the object - based on name and hashcode of first arg (if there is one)

Overrides:

hashCode in class Function

Returns:

Hash code

See Also:

ExpressionSymbol.hashCode()

equals

public boolean equals(Object obj)

Description copied from class: Function

Compare for equality

Overrides:

equals in class Function

Parameters:

obj - Other object to compare

Returns:

Return true if objects are equivalent

See Also:

ExpressionSymbol.equals(java.lang.Object)

isCardinalityDependent

public boolean isCardinalityDependent()

getCondition

public Expression getCondition()

setCondition

public void setCondition(Expression condition)

areAggregatesCardinalityDependent

public static boolean areAggregatesCardinalityDependent(Collection<AggregateSymbol> aggs)

respectsNulls

public boolean respectsNulls()

canStage

public boolean canStage()

isWindowed

public boolean isWindowed()

setWindowed

public void setWindowed(boolean isWindowed)