org.hsqldb

Class ExpressionAggregate

java.lang.Object

org.hsqldb.Expression

org.hsqldb.ExpressionAggregate

All Implemented Interfaces:

java.lang.Cloneable

public class ExpressionAggregate
extends Expression

Implementation of aggregate operations

Since:

1.9.0

Field Summary

Fields inherited from class org.hsqldb.Expression

BINARY, LEFT, RIGHT, TERNARY, UNARY

Method Summary

Modifier and Type	Method and Description
boolean	equals(Expression other)
java.lang.Object	getAggregatedValue(Session session, java.lang.Object currValue) Get the result of a SetFunction or an ordinary value
Expression	getCondition()
java.lang.String	getSQL() For use with CHECK constraints.
boolean	hasCondition()
HsqlList	resolveColumnReferences(Session session, RangeGroup rangeGroup, int rangeCount, RangeGroup[] rangeGroups, HsqlList unresolvedSet, boolean acceptsSequences)
void	resolveTypes(Session session, Expression parent)
void	setCondition(Expression e)
java.lang.Object	updateAggregatingValue(Session session, java.lang.Object currValue)

Methods inherited from class org.hsqldb.Expression

checkValidCheckConstraint, duplicate, equals, getColumn, getConstantValueNoCheck, getResult, getRowValue, getSubqueries, getTable, getType, getUnkeyedColumns, getValue, hashCode, isCorrelated, isFalse, isIndexable, isTrue, materialise, resolveCheckOrGenExpression, resolveColumnReferences, setCollation, testCondition

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, toString, wait, wait, wait

Method Detail

getSQL

public java.lang.String getSQL()

Description copied from class: Expression

For use with CHECK constraints. Under development. Currently supports a subset of expressions and is suitable for CHECK search conditions that refer only to the inserted/updated row. For full DDL reporting of VIEW select queries and CHECK search conditions, future improvements here are dependent upon improvements to SELECT query parsing, so that it is performed in a number of passes. An early pass should result in the query turned into an Expression tree that contains the information in the original SQL without any alterations, and with tables and columns all resolved. This Expression can then be preserved for future use. Table and column names that are not user-defined aliases should be kept as the HsqlName structures so that table or column renaming is reflected in the precompiled query.

Overrides:

getSQL in class Expression

resolveColumnReferences

public HsqlList resolveColumnReferences(Session session,
                                        RangeGroup rangeGroup,
                                        int rangeCount,
                                        RangeGroup[] rangeGroups,
                                        HsqlList unresolvedSet,
                                        boolean acceptsSequences)

Overrides:

resolveColumnReferences in class Expression

resolveTypes

public void resolveTypes(Session session,
                         Expression parent)

Overrides:

resolveTypes in class Expression

equals

public boolean equals(Expression other)

Overrides:

equals in class Expression

updateAggregatingValue

public java.lang.Object updateAggregatingValue(Session session,
                                               java.lang.Object currValue)

Overrides:

updateAggregatingValue in class Expression

getAggregatedValue

public java.lang.Object getAggregatedValue(Session session,
                                           java.lang.Object currValue)

Get the result of a SetFunction or an ordinary value

Overrides:

getAggregatedValue in class Expression

Parameters:

currValue - instance of set function or value

session - context

Returns:

object

getCondition

public Expression getCondition()

Overrides:

getCondition in class Expression

hasCondition

public boolean hasCondition()

Overrides:

hasCondition in class Expression

setCondition

public void setCondition(Expression e)

Overrides:

setCondition in class Expression