Package org.h2.expression.function.table

Class TableFunction

java.lang.Object

org.h2.expression.function.table.TableFunction

All Implemented Interfaces:

ExpressionWithVariableParameters, NamedExpression, HasSQL

Direct Known Subclasses:

ArrayTableFunction, CSVReadFunction, JavaTableFunction, LinkSchemaFunction

public abstract class TableFunction
extends Object
implements HasSQL, NamedExpression, ExpressionWithVariableParameters

A table value function.

Field Summary

Fields

Modifier and Type	Field	Description
protected Expression[]	args

Fields inherited from interface org.h2.util.HasSQL

ADD_PLAN_INFORMATION, DEFAULT_SQL_FLAGS, NO_CASTS, QUOTE_ONLY_WHEN_REQUIRED, REPLACE_LOBS_FOR_TRACE, TRACE_SQL_FLAGS

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	TableFunction(Expression[] args)

Method Summary

Modifier and Type	Method	Description
void	addParameter(Expression param)	Adds the parameter expression.
void	doneWithParameters()	This method must be called after all the parameters have been set.
StringBuilder	getSQL(StringBuilder builder, int sqlFlags)	Appends the SQL statement of this object to the specified builder.
abstract ResultInterface	getValue(SessionLocal session)	Get a result with.
abstract ResultInterface	getValueTemplate(SessionLocal session)	Get an empty result with the column names set.
abstract boolean	isDeterministic()	Whether the function always returns the same result for the same parameters.
void	optimize(SessionLocal session)	Try to optimize this table function

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.h2.util.HasSQL

getSQL, getTraceSQL

Methods inherited from interface org.h2.expression.function.NamedExpression

getName

Field Details

args

protected Expression[] args

Constructor Details

TableFunction

protected TableFunction(Expression[] args)

Method Details

addParameter

public void addParameter(Expression param)

Description copied from interface: ExpressionWithVariableParameters

Adds the parameter expression.

Specified by:

addParameter in interface ExpressionWithVariableParameters

Parameters:

param - the expression

doneWithParameters

public void doneWithParameters()
                        throws DbException

Description copied from interface: ExpressionWithVariableParameters

This method must be called after all the parameters have been set. It checks if the parameter count is correct when required by the implementation.

Specified by:

doneWithParameters in interface ExpressionWithVariableParameters

Throws:

DbException - if the parameter count is incorrect.

getValue

public abstract ResultInterface getValue(SessionLocal session)

Get a result with.

Parameters:

session - the session

Returns:

the result

getValueTemplate

public abstract ResultInterface getValueTemplate(SessionLocal session)

Get an empty result with the column names set.

Parameters:

session - the session

Returns:

the empty result

optimize

public void optimize(SessionLocal session)

Try to optimize this table function

Parameters:

session - the session

isDeterministic

public abstract boolean isDeterministic()

Whether the function always returns the same result for the same parameters.

Returns:

true if it does

getSQL

public StringBuilder getSQL(StringBuilder builder,
 int sqlFlags)

Description copied from interface: HasSQL

Appends the SQL statement of this object to the specified builder.

Specified by:

getSQL in interface HasSQL

Parameters:

builder - string builder

sqlFlags - formatting flags

Returns:

the specified string builder