org.apache.derby.impl.sql.compile
Class OrderedColumn

java.lang.Object
  org.apache.derby.impl.sql.compile.QueryTreeNode
      org.apache.derby.impl.sql.compile.OrderedColumn

All Implemented Interfaces:

Node, Visitable

Direct Known Subclasses:

GroupByColumn, OrderByColumn

public abstract class OrderedColumn
extends QueryTreeNode

An ordered column has position. It is an abstract class for group by and order by columns.

Field Summary

protected int	columnPosition
protected static int	UNMATCHEDPOSITION

Fields inherited from class org.apache.derby.impl.sql.compile.QueryTreeNode

AUTOINCREMENT_CREATE_MODIFY, AUTOINCREMENT_INC_INDEX, AUTOINCREMENT_IS_AUTOINCREMENT_INDEX, AUTOINCREMENT_START_INDEX, isPrivilegeCollectionRequired

Constructor Summary

OrderedColumn()

Method Summary

int	getColumnPosition() Get the position of this column
boolean	isAscending() Indicate whether this column is ascending or not.
boolean	isNullsOrderedLow() Indicate whether this column should be ordered NULLS low.
void	setColumnPosition(int columnPosition) Set the position of this column
java.lang.String	toString() Convert this object to a String.

Methods inherited from class org.apache.derby.impl.sql.compile.QueryTreeNode

accept, acceptChildren, bindOffsetFetch, bindRowMultiSet, bindUserCatalogType, bindUserType, checkReliability, checkReliability, convertDefaultNode, createTypeDependency, debugFlush, debugPrint, disablePrivilegeCollection, formatNodeString, foundString, generate, generateAuthorizeCheck, getBeginOffset, getClassFactory, getCompilerContext, getContextManager, getCursorInfo, getDataDictionary, getDependencyManager, getEndOffset, getExecutionFactory, getGenericConstantActionFactory, getIntProperty, getLanguageConnectionContext, getNodeFactory, getNodeType, getNullNode, getParameterTypes, getSchemaDescriptor, getSchemaDescriptor, getStatementType, getTableDescriptor, getTypeCompiler, init, init, init, init, init, init, init, init, init, init, init, init, init, init, isAtomic, isInstanceOf, isPrivilegeCollectionRequired, isSessionSchema, isSessionSchema, makeConstantAction, makeTableName, makeTableName, nodeHeader, orReliability, parseStatement, printLabel, printSubNodes, referencesSessionSchema, resolveTableToSynonym, setBeginOffset, setContextManager, setEndOffset, setNodeType, setRefActionInfo, stackPrint, treePrint, treePrint, verifyClassExist

Methods inherited from class java.lang.Object

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

Field Detail

UNMATCHEDPOSITION

protected static final int UNMATCHEDPOSITION

See Also:

Constant Field Values

columnPosition

protected int columnPosition

Constructor Detail

OrderedColumn

public OrderedColumn()

Method Detail

isAscending

public boolean isAscending()

Indicate whether this column is ascending or not. By default assume that all ordered columns are necessarily ascending. If this class is inherited by someone that can be desceneded, they are expected to override this method.

Returns:

true

isNullsOrderedLow

public boolean isNullsOrderedLow()

Indicate whether this column should be ordered NULLS low. By default we assume that all ordered columns are ordered with NULLS higher than non-null values. If this class is inherited by someone that can be specified to have NULLs ordered lower than non-null values, they are expected to override this method.

Returns:

false

toString

public java.lang.String toString()

Convert this object to a String. See comments in QueryTreeNode.java for how this should be done for tree printing.

Overrides:

toString in class QueryTreeNode

Returns:

This object as a String

getColumnPosition

public int getColumnPosition()

Get the position of this column

Returns:

The position of this column

setColumnPosition

public void setColumnPosition(int columnPosition)

Set the position of this column