org.hsqldb

Class Expression

java.lang.Object

org.hsqldb.Expression

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

ExpressionAccessor, ExpressionAggregate, ExpressionArithmetic, ExpressionArrayAggregate, ExpressionColumn, ExpressionColumnAccessor, ExpressionLogical, ExpressionOp, ExpressionOrderBy, ExpressionTable, ExpressionValue, FunctionSQL, FunctionSQLInvoked

public class Expression
extends java.lang.Object
implements java.lang.Cloneable

Expression class.

Since:

1.9.0

Field Summary

Fields

Modifier and Type	Field and Description
static int	BINARY
static int	LEFT
static int	RIGHT
static int	TERNARY
static int	UNARY

Method Summary

Modifier and Type	Method and Description
void	checkValidCheckConstraint() checkValidCheckConstraint
Expression	duplicate()
boolean	equals(Expression other)
boolean	equals(java.lang.Object other)
java.lang.Object	getAggregatedValue(Session session, java.lang.Object currValue)
ColumnSchema	getColumn()
Expression	getCondition()
java.lang.Object	getConstantValueNoCheck(Session session)
Result	getResult(Session session)
java.lang.Object[]	getRowValue(Session session)
java.lang.String	getSQL() For use with CHECK constraints.
OrderedHashSet	getSubqueries()
Table	getTable()
int	getType() Returns the type of expression
OrderedHashSet	getUnkeyedColumns(OrderedHashSet unresolvedSet)
java.lang.Object	getValue(Session session)
boolean	hasCondition()
int	hashCode()
boolean	isCorrelated() isCorrelated
boolean	isFalse()
boolean	isIndexable(RangeVariable range)
boolean	isTrue()
void	materialise(Session session)
void	resolveCheckOrGenExpression(Session session, RangeGroup rangeGroup, boolean isCheck)
HsqlList	resolveColumnReferences(Session session, RangeGroup rangeGroup, int rangeCount, RangeGroup[] rangeGroups, HsqlList unresolvedSet, boolean acceptsSequences)
HsqlList	resolveColumnReferences(Session session, RangeGroup rangeGroup, RangeGroup[] rangeGroups, HsqlList unresolvedSet) resolve tables and collect unresolved column expressions
void	resolveTypes(Session session, Expression parent)
void	setCollation(Collation collation)
void	setCondition(Expression e)
boolean	testCondition(Session session)
java.lang.Object	updateAggregatingValue(Session session, java.lang.Object currValue)

Methods inherited from class java.lang.Object

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

Field Detail

LEFT

public static final int LEFT

See Also:

Constant Field Values

RIGHT

public static final int RIGHT

See Also:

Constant Field Values

UNARY

public static final int UNARY

See Also:

Constant Field Values

BINARY

public static final int BINARY

See Also:

Constant Field Values

TERNARY

public static final int TERNARY

See Also:

Constant Field Values

Method Detail

getSQL

public java.lang.String getSQL()

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.

equals

public boolean equals(Expression other)

equals

public boolean equals(java.lang.Object other)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

getType

public int getType()

Returns the type of expression

resolveColumnReferences

public HsqlList resolveColumnReferences(Session session,
                                        RangeGroup rangeGroup,
                                        RangeGroup[] rangeGroups,
                                        HsqlList unresolvedSet)

resolve tables and collect unresolved column expressions

resolveColumnReferences

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

getUnkeyedColumns

public OrderedHashSet getUnkeyedColumns(OrderedHashSet unresolvedSet)

resolveTypes

public void resolveTypes(Session session,
                         Expression parent)

getColumn

public ColumnSchema getColumn()

getTable

public Table getTable()

materialise

public void materialise(Session session)

getConstantValueNoCheck

public java.lang.Object getConstantValueNoCheck(Session session)

getRowValue

public java.lang.Object[] getRowValue(Session session)

getValue

public java.lang.Object getValue(Session session)

getResult

public Result getResult(Session session)

testCondition

public boolean testCondition(Session session)

isTrue

public boolean isTrue()

isFalse

public boolean isFalse()

isIndexable

public boolean isIndexable(RangeVariable range)

resolveCheckOrGenExpression

public void resolveCheckOrGenExpression(Session session,
                                        RangeGroup rangeGroup,
                                        boolean isCheck)

getSubqueries

public OrderedHashSet getSubqueries()

isCorrelated

public boolean isCorrelated()

isCorrelated

checkValidCheckConstraint

public void checkValidCheckConstraint()

checkValidCheckConstraint

duplicate

public Expression duplicate()

updateAggregatingValue

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

getAggregatedValue

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

getCondition

public Expression getCondition()

hasCondition

public boolean hasCondition()

setCondition

public void setCondition(Expression e)

setCollation

public void setCollation(Collation collation)