isql.expression
Class AggregateFunction

java.lang.Object
  isql.expression.AggregateFunction

All Implemented Interfaces:

ISimpleExpression, IExpression

public class AggregateFunction
extends java.lang.Object
implements ISimpleExpression

function to aggregate rows of the view (for example SUM, AVERAGE...). It works in conjunction with the group by clause

Author:

SHZ Oct 1, 2007

Constructor Summary

AggregateFunction(IExpression expression, Groups groups, AggregateType aggregateType)

Method Summary

java.util.Set<ColumnKey>	getInvolvedColumns() Returns the table columns named in the expression
ITypedValue	getResult() Get the result of the expression (can be a constant or an array)
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AggregateFunction

public AggregateFunction(IExpression expression,
                         Groups groups,
                         AggregateType aggregateType)

Method Detail

getResult

public ITypedValue getResult()
                      throws ISQLException

Description copied from interface: IExpression

Get the result of the expression (can be a constant or an array)

Specified by:

getResult in interface IExpression

Returns:

the result

Throws:

ISQLException

getInvolvedColumns

public java.util.Set<ColumnKey> getInvolvedColumns()

Description copied from interface: IExpression

Returns the table columns named in the expression

Specified by:

getInvolvedColumns in interface IExpression

Returns:

the identifiers of the columns

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object