org.apache.derby.impl.sql.compile

Class IntersectOrExceptNode

java.lang.Object

org.apache.derby.impl.sql.compile.QueryTreeNode

org.apache.derby.impl.sql.compile.ResultSetNode

org.apache.derby.impl.sql.compile.FromTable

org.apache.derby.impl.sql.compile.TableOperatorNode

org.apache.derby.impl.sql.compile.SetOperatorNode

org.apache.derby.impl.sql.compile.IntersectOrExceptNode

All Implemented Interfaces:

Node, Optimizable, Visitable

public class IntersectOrExceptNode
extends SetOperatorNode

A IntersectOrExceptNode represents an INTERSECT or EXCEPT DML statement.

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	addNewNodesCalled
static int	EXCEPT_OP
private int[]	intermediateOrderByColumns
private int[]	intermediateOrderByDirection
private boolean[]	intermediateOrderByNullsLow
static int	INTERSECT_OP
private int	opType

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

all, fetchFirst, hasJDBClimitClause, offset, orderByLists

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

leftOptimizer, leftResultSet, rightOptimizer, rightResultSet

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

ADD_PLAN, bestAccessPath, bestCostEstimate, bestSortAvoidancePath, correlationName, corrTableName, currentAccessPath, hashKeyColumns, initialCapacity, level, LOAD_PLAN, loadFactor, maxCapacity, origTableName, REMOVE_PLAN, tableNumber, tableProperties, trulyTheBestAccessPath, userSpecifiedJoinStrategy

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

costEstimate, cursorTargetTable, finalCostEstimate, insertSource, optimizer, referencedTableMap, resultColumns, resultSetNumber, scratchCostEstimate, statementResultSet

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

AUTOINCREMENT_CREATE_MODIFY, AUTOINCREMENT_INC_INDEX, AUTOINCREMENT_IS_AUTOINCREMENT_INDEX, AUTOINCREMENT_START_INDEX

Constructor Summary

Constructors

Constructor and Description
IntersectOrExceptNode()

Method Summary

Modifier and Type	Method and Description
private ResultSetNode	addNewNodes() Add any new ResultSetNodes that are necessary to the tree.
CostEstimate	estimateCost(OptimizablePredicateList predList, ConglomerateDescriptor cd, CostEstimate outerCost, Optimizer optimizer, RowOrdering rowOrdering) Estimate the cost of scanning this Optimizable using the given predicate list with the given conglomerate.
void	generate(ActivationClassBuilder acb, MethodBuilder mb) Generate the code.
CostEstimate	getFinalCostEstimate() Get the final CostEstimate for this FromTable.
(package private) java.lang.String	getOperatorName()
private int	getOpType()
(package private) double	getRowCountEstimate(double leftRowCount, double rightRowCount)
(package private) double	getSingleScanRowCountEstimate(double leftSingleScanRowCount, double rightSingleScanRowCount)
void	init(java.lang.Object opType, java.lang.Object leftResult, java.lang.Object rightResult, java.lang.Object all, java.lang.Object tableProperties) Initializer for a SetOperatorNode.
Optimizable	modifyAccessPath(JBitSet outerTables) Modify the access path for this Optimizable, as necessary.
ResultSetNode	modifyAccessPaths() Modify the access paths according to the decisions the optimizer made.
ResultSetNode	preprocess(int numTables, GroupByList gbl, FromList fromList) Push order by lists down to the children so that we can implement the intersect/except by scan of the two sorted inputs.
private void	pushOrderingDown(ResultSetNode rsn)

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

bindExpressions, bindResultColumns, bindResultColumns, bindTargetExpressions, bindUntypedNullsToResultColumns, ensurePredicateList, flattenableInFromSubquery, getFromTableByName, getLeftOptPredicateList, getParamColumnTypes, getRightOptPredicateList, hasUnPushedPredicates, init, modifyAccessPath, performMaterialization, printSubNodes, pullOptPredicates, pushOffsetFetchFirst, pushOptPredicate, pushOrderByList, replaceOrForbidDefaults, setParamColumnTypes, setResultToBooleanTrueNode, toString, verifySelectStarSubquery

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

acceptChildren, adjustForSortElimination, adjustForSortElimination, bindExpressionsWithTables, bindNonVTITables, bindVTITables, decrementLevel, getExposedName, getLeftmostResultSet, getLeftResultSet, getRightResultSet, init, needsSpecialRCLBinding, optimize, optimizeSource, projectResultColumns, referencesSessionSchema, referencesTarget, rejectParameters, setLeftmostResultSet, setLevel, setNestedInParens, setReferencedColumns, updateBestPlanMap, verifyProperties

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

assignCostEstimate, canBeOrdered, considerSortAvoidancePath, convertAbsoluteToRelativeColumnPosition, cursorTargetTable, feasibleJoinStrategy, fillInReferencedTableMap, flatten, forUpdate, getBaseTableName, getBestAccessPath, getBestSortAvoidancePath, getCorrelationName, getCostEstimate, getCurrentAccessPath, getLevel, getName, getNumColumnsReturned, getOrigTableName, getProperties, getResultColumnsForList, getSchemaDescriptor, getSchemaDescriptor, getScratchCostEstimate, getTableDescriptor, getTableName, getTableNumber, getTrulyTheBestAccessPath, getUserSpecifiedJoinStrategy, hashKeyColumns, hasLargeObjectColumns, hasTableNumber, init, initAccessPaths, initialCapacity, isBaseTable, isCoveringIndex, isFlattenableJoinNode, isJoinColumnForRightOuterJoin, isMaterializable, isOneRowScan, isTargetTable, legalJoinOrder, loadFactor, LOJ_reorderable, markUpdatableByCursor, maxCapacity, memoryUsageOK, nextAccessPath, optimizeIt, optimizeSubqueries, pushExpressions, rememberAsBest, rememberJoinStrategyAsBest, rememberSortAvoidancePath, resetJoinStrategies, setCostEstimate, setHashKeyColumns, setOrigTableName, setProperties, setTableNumber, startOptimizing, supportsMultipleInstantiations, tellRowOrderingAboutConstantColumns, transformOuterJoins, uniqueJoin

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

addNewPredicate, assignResultSetNumber, changeAccessPath, columnTypesAndLengthsMatch, considerMaterialization, enhanceRCLForInsert, generateNormalizationResultSet, generateResultSet, genProjectRestrict, genProjectRestrict, genProjectRestrictForReordering, getAllResultColumns, getCostEstimate, getCursorTargetTable, getFromList, getMatchingColumn, getNewCostEstimate, getOptimizer, getOptimizerImpl, getRCLForInsert, getReferencedTableMap, getResultColumns, getResultSetNumber, isNotExists, isOneRowResultSet, isOrderedOn, isPossibleDistinctScan, isUpdatableCursor, LOJgetReferencedTables, makeResultDescription, makeResultDescriptors, markAsCursorTargetTable, markForDistinctScan, markStatementResultSet, modifyAccessPaths, notCursorTargetTable, notFlattenableJoin, numDistinctAggregates, parseDefault, rejectXMLValues, renameGeneratedResultNames, returnsAtMostOneRow, setInsertSource, setReferencedTableMap, setResultColumns, setTableConstructorTypes, subqueryReferencesTarget, updateTargetLockMode

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

accept, bindOffsetFetch, bindRowMultiSet, bindUserCatalogType, bindUserType, checkReliability, checkReliability, convertDefaultNode, createTypeDependency, debugFlush, debugPrint, disablePrivilegeCollection, formatNodeString, foundString, 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, isAtomic, isInstanceOf, isPrivilegeCollectionRequired, isSessionSchema, isSessionSchema, makeConstantAction, makeTableName, makeTableName, nodeHeader, orReliability, parseStatement, printLabel, 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

Methods inherited from interface org.apache.derby.iapi.sql.compile.Optimizable

getDataDictionary, getReferencedTableMap, getResultSetNumber

Field Detail

opType

private int opType

INTERSECT_OP

public static final int INTERSECT_OP

See Also:

Constant Field Values

EXCEPT_OP

public static final int EXCEPT_OP

See Also:

Constant Field Values

addNewNodesCalled

private boolean addNewNodesCalled

intermediateOrderByColumns

private int[] intermediateOrderByColumns

intermediateOrderByDirection

private int[] intermediateOrderByDirection

intermediateOrderByNullsLow

private boolean[] intermediateOrderByNullsLow

Constructor Detail

IntersectOrExceptNode

public IntersectOrExceptNode()

Method Detail

init

public void init(java.lang.Object opType,
                 java.lang.Object leftResult,
                 java.lang.Object rightResult,
                 java.lang.Object all,
                 java.lang.Object tableProperties)
          throws StandardException

Initializer for a SetOperatorNode.

Specified by:

init in interface Node

Overrides:

init in class QueryTreeNode

Parameters:

leftResult - The ResultSetNode on the left side of this union

rightResult - The ResultSetNode on the right side of this union

all - Whether or not this is an ALL.

tableProperties - Properties list associated with the table

Throws:

StandardException - Thrown on error

getOpType

private int getOpType()

preprocess

public ResultSetNode preprocess(int numTables,
                                GroupByList gbl,
                                FromList fromList)
                         throws StandardException

Push order by lists down to the children so that we can implement the intersect/except by scan of the two sorted inputs.

Overrides:

preprocess in class SetOperatorNode

Parameters:

numTables - Number of tables in the DML Statement

gbl - The group by list, if any

fromList - The from list, if any

Returns:

The preprocessed ResultSetNode that can be optimized

Throws:

StandardException - Thrown on error

pushOrderingDown

private void pushOrderingDown(ResultSetNode rsn)
                       throws StandardException

Throws:

StandardException

estimateCost

public CostEstimate estimateCost(OptimizablePredicateList predList,
                                 ConglomerateDescriptor cd,
                                 CostEstimate outerCost,
                                 Optimizer optimizer,
                                 RowOrdering rowOrdering)
                          throws StandardException

Description copied from interface: Optimizable

Estimate the cost of scanning this Optimizable using the given predicate list with the given conglomerate. It is assumed that the predicate list has already been classified. This cost estimate is just for one scan, not for the life of the query.

Specified by:

estimateCost in interface Optimizable

Overrides:

estimateCost in class FromTable

Parameters:

predList - The predicate list to optimize against

cd - The conglomerate descriptor to get the cost of

outerCost - The estimated cost of the part of the plan outer to this optimizable.

optimizer - The optimizer to use to help estimate the cost

rowOrdering - The row ordering for all the tables in the join order, including this one.

Returns:

The estimated cost of doing the scan

Throws:

StandardException - Thrown on error

See Also:

Optimizable.estimateCost(org.apache.derby.iapi.sql.compile.OptimizablePredicateList, org.apache.derby.iapi.sql.dictionary.ConglomerateDescriptor, org.apache.derby.iapi.sql.compile.CostEstimate, org.apache.derby.iapi.sql.compile.Optimizer, org.apache.derby.iapi.sql.compile.RowOrdering)

modifyAccessPath

public Optimizable modifyAccessPath(JBitSet outerTables)
                             throws StandardException

Description copied from interface: Optimizable

Modify the access path for this Optimizable, as necessary. This includes things like adding a result set to translate from index rows to base rows

Specified by:

modifyAccessPath in interface Optimizable

Overrides:

modifyAccessPath in class TableOperatorNode

Parameters:

outerTables - Bit map of the tables that are outer to this one in the join order.

Returns:

The (potentially new) Optimizable at the top of the tree.

Throws:

StandardException - Thrown on error

See Also:

Optimizable.modifyAccessPath(org.apache.derby.iapi.util.JBitSet)

modifyAccessPaths

public ResultSetNode modifyAccessPaths()
                                throws StandardException

Description copied from class: ResultSetNode

Modify the access paths according to the decisions the optimizer made. This can include adding project/restrict nodes, index-to-base-row nodes, etc.

Overrides:

modifyAccessPaths in class TableOperatorNode

Returns:

The modified query tree

Throws:

StandardException - Thrown on error

See Also:

ResultSetNode.modifyAccessPaths()

addNewNodes

private ResultSetNode addNewNodes()
                           throws StandardException

Add any new ResultSetNodes that are necessary to the tree. We wait until after optimization to do this in order to make it easier on the optimizer.

Returns:

(Potentially new) head of the ResultSetNode tree.

Throws:

StandardException - Thrown on error

generate

public void generate(ActivationClassBuilder acb,
                     MethodBuilder mb)
              throws StandardException

Generate the code.

Overrides:

generate in class QueryTreeNode

Parameters:

acb - The ActivationClassBuilder for the class being built

mb - The method for the generated code to go into

Throws:

StandardException - Thrown on error

getFinalCostEstimate

public CostEstimate getFinalCostEstimate()
                                  throws StandardException

Description copied from class: FromTable

Get the final CostEstimate for this FromTable.

Overrides:

getFinalCostEstimate in class FromTable

Returns:

The final CostEstimate for this IntersectOrExceptNode, which is the sum of the two child costs. The final number of rows depends on whether this is an INTERSECT or EXCEPT (see getRowCountEstimate() in this class for more).

Throws:

StandardException

See Also:

Get the final CostEstimate for this IntersectOrExceptNode.

getOperatorName

java.lang.String getOperatorName()

Specified by:

getOperatorName in class SetOperatorNode

Returns:

the operator name: "UNION", "INTERSECT", or "EXCEPT"

getRowCountEstimate

double getRowCountEstimate(double leftRowCount,
                           double rightRowCount)

getSingleScanRowCountEstimate

double getSingleScanRowCountEstimate(double leftSingleScanRowCount,
                                     double rightSingleScanRowCount)