org.hsqldb

Class ExpressionOp

java.lang.Object

org.hsqldb.Expression

org.hsqldb.ExpressionOp

All Implemented Interfaces:

java.lang.Cloneable

public class ExpressionOp
extends Expression

Implementation of CAST, CASE, LIMIT and ZONE 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
static Expression	getCastExpression(Session session, Expression e, Type dataType)
java.lang.String	getSQL() For use with CHECK constraints.
java.lang.Object	getValue(Session session)
HsqlList	resolveColumnReferences(Session session, RangeGroup rangeGroup, int rangeCount, RangeGroup[] rangeGroups, HsqlList unresolvedSet, boolean acceptsSequences)
void	resolveTypes(Session session, Expression parent)

Methods inherited from class org.hsqldb.Expression

checkValidCheckConstraint, duplicate, equals, equals, getAggregatedValue, getColumn, getCondition, getConstantValueNoCheck, getResult, getRowValue, getSubqueries, getTable, getType, getUnkeyedColumns, hasCondition, hashCode, isCorrelated, isFalse, isIndexable, isTrue, materialise, resolveCheckOrGenExpression, resolveColumnReferences, setCollation, setCondition, testCondition, updateAggregatingValue

Methods inherited from class java.lang.Object

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

Method Detail

getCastExpression

public static Expression getCastExpression(Session session,
                                           Expression e,
                                           Type dataType)

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

getValue

public java.lang.Object getValue(Session session)

Overrides:

getValue in class Expression