Apache Derby Database Engine and Embedded JDBC Driver 10.17.1.0 · org.apache.derby.impl.sql.compile.FromTable

Modifier and Type	Field and Description
private int	_mergeTableID for resolving column references in MERGE statements in tough cases
protected static final short	ADD_PLAN
pack-priv AccessPathImpl	bestAccessPath
protected CostEstimate	bestCostEstimate
private HashMap<Object, AccessPathImpl>	bestPlanMap Set of object->trulyTheBestAccessPath mappings used to keep track of which of this Optimizable's "trulyTheBestAccessPath" was the best with respect to a specific outer query or ancestor node.
pack-priv AccessPathImpl	bestSortAvoidancePath
private boolean	considerSortAvoidancePath
pack-priv String	correlationName
pack-priv TableName	corrTableName
pack-priv AccessPathImpl	currentAccessPath
pack-priv int[]	hashKeyColumns
pack-priv int	initialCapacity
private int	joinStrategyNumber
pack-priv int	level
protected static final short	LOAD_PLAN
pack-priv float	loadFactor
pack-priv int	maxCapacity
protected TableName	origTableName the original unbound table name
private double	perRowUsage
protected static final short	REMOVE_PLAN Operations that can be performed on bestPlanMap.
pack-priv int	tableNumber
pack-priv Properties	tableProperties
pack-priv AccessPathImpl	trulyTheBestAccessPath
protected String	userSpecifiedJoinStrategy

Access	Constructor and Description
pack-priv	FromTable(String The correlation name correlationName, Properties Properties list associated with the table tableProperties, ContextManager The context manager cm) Constructor for a table in a FROM list.

Method Summary

Modifier and Type	Method and Description
pack-priv void	acceptChildren(Visitor the visitor v) Overrides org.apache.derby.impl.sql.compile.ResultSetNode.acceptChildren. Accept the visitor for all visitable children of this node.
protected void	assignCostEstimate(CostEstimate newCostEstimate) Assign the cost estimate in this node to the given cost estimate.
protected boolean	canBeOrdered() Most Optimizables cannot be ordered
pack-priv boolean	Returns: true if some columns in this table are updatable. columnsAreUpdatable() Return true if some columns in this table are updatable.
public boolean	considerSortAvoidancePath() Implements org.apache.derby.iapi.sql.compile.Optimizable.considerSortAvoidancePath. Check whether this optimizable's sort avoidance path should be considered.
public int	convertAbsoluteToRelativeColumnPosition(int The absolute 0-based column position for the column. absolutePosition) Implements org.apache.derby.iapi.sql.compile.Optimizable.convertAbsoluteToRelativeColumnPosition. Convert an absolute to a relative 0-based column position.
protected boolean	Returns: true/false cursorTargetTable() Is this a table that has a FOR UPDATE clause.
pack-priv void	decrementLevel(int The amount to decrement by. decrement) Implements abstract org.apache.derby.impl.sql.compile.ResultSetNode.decrementLevel. Decrement (query block) level (0-based) for this FromTable.
public CostEstimate	estimateCost(OptimizablePredicateList The predicate list to optimize against predList, ConglomerateDescriptor The conglomerate descriptor to get the cost of cd, CostEstimate The estimated cost of the part of the plan outer to this optimizable. outerCost, Optimizer The optimizer to use to help estimate the cost optimizer, RowOrdering The row ordering for all the tables in the join order, including this one. rowOrdering) Implements org.apache.derby.iapi.sql.compile.Optimizable.estimateCost. Estimate the cost of scanning this Optimizable using the given predicate list with the given conglomerate.
public boolean	feasibleJoinStrategy(OptimizablePredicateList The predicate list that has been pushed down to this optimizable predList, Optimizer The optimizer to use. optimizer) Implements org.apache.derby.iapi.sql.compile.Optimizable.feasibleJoinStrategy. Is the current proposed join strategy for this optimizable feasible given the predicate list?
pack-priv void	fillInReferencedTableMap(JBitSet The table map to fill in. passedMap) Overrides org.apache.derby.impl.sql.compile.ResultSetNode.fillInReferencedTableMap. Fill the referencedTableMap with this ResultSetNode.
pack-priv FromList	Returns: FromList The fromList from the underlying SelectNode. flatten(ResultColumnList The RCL from the outer query rcl, PredicateList PredicateList to append wherePredicates to. outerPList, SubqueryList The SubqueryList from the outer query sql, GroupByList The group by list, if any gbl, ValueNode The HAVING clause, if any havingClause) Flatten this FromTable into the outer query block.
public boolean	forUpdate() Implements org.apache.derby.iapi.sql.compile.Optimizable.forUpdate. Return true if this is the target table of an update
public String	getBaseTableName() Implements org.apache.derby.iapi.sql.compile.Optimizable.getBaseTableName. Get the table name of this Optimizable.
public AccessPath	getBestAccessPath() Implements org.apache.derby.iapi.sql.compile.Optimizable.getBestAccessPath. Get the best access path for this Optimizable.
public AccessPath	getBestSortAvoidancePath() Implements org.apache.derby.iapi.sql.compile.Optimizable.getBestSortAvoidancePath. Get the best sort-avoidance path for this Optimizable.
public String	getCorrelationName() Get this table's correlation name, if any.
protected CostEstimate	getCostEstimate(Optimizer optimizer)
public AccessPath	getCurrentAccessPath() Implements org.apache.derby.iapi.sql.compile.Optimizable.getCurrentAccessPath. Get the current access path under consideration for this Optimizable
pack-priv String	Returns: The exposed name of this table. getExposedName() Get the exposed name for this table, which is the name that can be used to refer to it in the rest of the query.
pack-priv CostEstimate	Returns: The final CostEstimate for this FromTable, which is the costEstimate of trulyTheBestAccessPath if there is one. If there's no trulyTheBestAccessPath for this node, then we just return the value stored in costEstimate as a default. getFinalCostEstimate() Overrides org.apache.derby.impl.sql.compile.ResultSetNode.getFinalCostEstimate. Get the final CostEstimate for this FromTable.
pack-priv FromTable	Returns: The FromTable, if any, with the exposed name. getFromTableByName(String The specified name to search for as an exposed name. name, String Schema name, if non-null. schemaName, boolean Whether or not we need an exact match on specified schema and table names or match on table id. exactMatch) Overrides org.apache.derby.impl.sql.compile.ResultSetNode.getFromTableByName. Determine whether or not the specified name is an exposed name in the current query block.
pack-priv int	Returns: int The query block level for this FromTable. getLevel() Get the (query block) level (0-based) for this FromTable.
pack-priv int	getMergeTableID() get the merge table id
public String	getName() Implements org.apache.derby.iapi.sql.compile.Optimizable.getName. Get the (exposed) name of this Optimizable
public int	getNumColumnsReturned() Implements org.apache.derby.iapi.sql.compile.Optimizable.getNumColumnsReturned. Get the number of the number of columns returned by this Optimizable.
pack-priv TableName	Returns: TableName the original or unbound tablename getOrigTableName() Gets the original or unbound table name for this FromTable.
private double	getPerRowUsage()
public Properties	getProperties() Implements org.apache.derby.iapi.sql.compile.Optimizable.getProperties. Get the Properties list, if any, associated with this optimizable.
pack-priv ResultColumnList	Returns: ResultColumnList List of result columns from this table. getResultColumnsForList(TableName The qualifier on the "*" allTableName, ResultColumnList inputRcl, TableName tableName) Return a ResultColumnList with all of the columns in this table.
pack-priv SchemaDescriptor	Returns: Schema Descriptor getSchemaDescriptor() Get a schema descriptor for the given table.
pack-priv SchemaDescriptor	Returns: Schema Descriptor getSchemaDescriptor(TableName the table name tableName) Get a schema descriptor for the given table.
protected CostEstimate	getScratchCostEstimate(Optimizer optimizer)
public TableDescriptor	getTableDescriptor() Implements org.apache.derby.iapi.sql.compile.Optimizable.getTableDescriptor. Get the table descriptor for this table (if any).
pack-priv TableName	Returns: a TableName node representing this FromTable. getTableName() Return a TableName node representing this FromTable.
public int	getTableNumber() Implements org.apache.derby.iapi.sql.compile.Optimizable.getTableNumber. Get this Optimizable's table number
public AccessPath	getTrulyTheBestAccessPath() Implements org.apache.derby.iapi.sql.compile.Optimizable.getTrulyTheBestAccessPath. Get the best access path overall for this Optimizable.
pack-priv String	Returns: The user specified join strategy, if any for this table. getUserSpecifiedJoinStrategy() Return the user specified join strategy, if any for this table.
public int[]	hashKeyColumns() Implements org.apache.derby.iapi.sql.compile.Optimizable.hashKeyColumns. Return the hash key column numbers, for hash join strategy
public boolean	Returns: `true` if at least one large object column is referenced, `false` otherwise hasLargeObjectColumns() Implements org.apache.derby.iapi.sql.compile.Optimizable.hasLargeObjectColumns. Check if any columns containing large objects (BLOBs or CLOBs) are referenced in this table.
public boolean	hasTableNumber() Implements org.apache.derby.iapi.sql.compile.Optimizable.hasTableNumber. Return true if this Optimizable has a table number
public void	initAccessPaths(Optimizer The optimizer being used. optimizer) Implements org.apache.derby.iapi.sql.compile.Optimizable.initAccessPaths. Init the access paths for this optimizable.
public int	initialCapacity() Implements org.apache.derby.iapi.sql.compile.Optimizable.initialCapacity. Return the initial capacity of the hash table, for hash join strategy
public boolean	isBaseTable() Implements org.apache.derby.iapi.sql.compile.Optimizable.isBaseTable. Tell whether this Optimizable represents a base table
public boolean	isCoveringIndex(ConglomerateDescriptor ConglomerateDesriptor for index to consider cd) Implements org.apache.derby.iapi.sql.compile.Optimizable.isCoveringIndex. Return whether or not this is a covering index.
pack-priv boolean	Returns: boolean Whether or not this FromTable can be flattened. isFlattenableJoinNode() Is this FromTable a JoinNode which can be flattened into the parents FromList.
pack-priv void	isJoinColumnForRightOuterJoin(ResultColumn rc) No-op in FromTable.
public boolean	isMaterializable() Implements org.apache.derby.iapi.sql.compile.Optimizable.isMaterializable. Tell whether this Optimizable is materializable
public boolean	isOneRowScan() Implements org.apache.derby.iapi.sql.compile.Optimizable.isOneRowScan. Will the optimizable return at most 1 row per scan?
public boolean	isTargetTable() Implements org.apache.derby.iapi.sql.compile.Optimizable.isTargetTable. Is the optimizable the target table of an update or delete?
public boolean	legalJoinOrder(JBitSet The tables that have been placed so far in the join order. assignedTableMap) Implements org.apache.derby.iapi.sql.compile.Optimizable.legalJoinOrder. Can this Optimizable appear at the current location in the join order.
public float	loadFactor() Implements org.apache.derby.iapi.sql.compile.Optimizable.loadFactor. Return the load factor of the hash table, for hash join strategy
pack-priv boolean	LOJ_reorderable(int numTables) no LOJ reordering for this FromTable.
protected void	markUpdatableByCursor(List<String> A list representing the columns that can be updated. updateColumns) Mark as updatable all the columns in the result column list of this FromBaseTable that match the columns in the given update column list.
public int	maxCapacity(JoinStrategy joinStrategy, int The maximum number of bytes to be used. Ignored if the user has set a maximum number of rows for the Optimizable. maxMemoryPerTable) Implements org.apache.derby.iapi.sql.compile.Optimizable.maxCapacity. Return the maximum capacity of the hash table, for hash join strategy
public boolean	memoryUsageOK(double rowCount, int maxMemoryPerTable) Implements org.apache.derby.iapi.sql.compile.Optimizable.memoryUsageOK.
public Optimizable	modifyAccessPath(JBitSet Bit map of the tables that are outer to this one in the join order. outerTables) Implements org.apache.derby.iapi.sql.compile.Optimizable.modifyAccessPath. Modify the access path for this Optimizable, as necessary.
pack-priv boolean	needsSpecialRCLBinding()
public boolean	nextAccessPath(Optimizer Optimizer to use. optimizer, OptimizablePredicateList The predicate list for this optimizable. The optimizer always passes null, and it is up to the optimizable object to pass along its own predicate list, if appropriate, when delegating this method. predList, RowOrdering The row ordering for all the outer tables in the join order. This method will add the ordering of the next access path to the given RowOrdering. rowOrdering) Implements org.apache.derby.iapi.sql.compile.Optimizable.nextAccessPath. Choose the next access path to evaluate for this Optimizable.
public CostEstimate	optimizeIt(Optimizer Optimizer to use. optimizer, OptimizablePredicateList The predicate list to optimize against predList, CostEstimate The CostEstimate for the outer tables in the join order, telling how many times this Optimizable will be scanned. outerCost, RowOrdering The row ordering for all the tables in the join order, including this one. rowOrdering) Implements org.apache.derby.iapi.sql.compile.Optimizable.optimizeIt. Choose the best access path for this Optimizable.
pack-priv void	optimizeSubqueries(DataDictionary dd, double rowCount) Optimize any subqueries that haven't been optimized any where else.
public void	pullOptPredicates(OptimizablePredicateList The list to put the pulled predicates in. optimizablePredicates) Implements org.apache.derby.iapi.sql.compile.Optimizable.pullOptPredicates. Pull all the OptimizablePredicates from this Optimizable and put them in the given OptimizablePredicateList.
pack-priv void	pushExpressions(PredicateList The PredicateList. predicateList) Push expressions down to the first ResultSetNode which can do expression evaluation and has the same referenced table map.
public boolean	pushOptPredicate(OptimizablePredicate OptimizablePredicate to push down. optimizablePredicate) Implements org.apache.derby.iapi.sql.compile.Optimizable.pushOptPredicate. Push an OptimizablePredicate down, if this node accepts it.
public void	rememberAsBest(int The type of plan (one of Optimizer.NORMAL_PLAN or Optimizer.SORT_AVOIDANCE_PLAN) planType, Optimizer The OptimizerImpl that is telling this Optimizable to remember its current path as "truly the best". optimizer) Implements org.apache.derby.iapi.sql.compile.Optimizable.rememberAsBest. Remember the current access path as the best one (so far).
public void	rememberJoinStrategyAsBest(AccessPath ap) Implements org.apache.derby.iapi.sql.compile.Optimizable.rememberJoinStrategyAsBest. Remember the current join strategy as the best one so far in this join order.
public void	rememberSortAvoidancePath() Implements org.apache.derby.iapi.sql.compile.Optimizable.rememberSortAvoidancePath. Mark this optimizable so that its sort avoidance path will be considered.
protected void	resetJoinStrategies(Optimizer optimizer) This method is called when this table is placed in a potential join order, or when a new conglomerate is being considered.
protected void	setCostEstimateCost(CostEstimate newCostEstimate) Set the cost estimate in this node to the given cost estimate.
public void	setHashKeyColumns(int[] columnNumbers) Implements org.apache.derby.iapi.sql.compile.Optimizable.setHashKeyColumns. Set the hash key column numbers, for hash join strategy
pack-priv void	setLevel(int The query block level for this FromTable. level) Set the (query block) level (0-based) for this FromTable.
pack-priv void	setMergeTableID(int mergeTableID) set the merge table id
pack-priv void	setOrigTableName(TableName the unbound table name tableName) Sets the original or unbound table name for this FromTable.
public void	setProperties(Properties The Properties list for this optimizable. tableProperties) Implements org.apache.derby.iapi.sql.compile.Optimizable.setProperties. Set the Properties list for this optimizalbe.
pack-priv void	setTableNumber(int The table # for this table. tableNumber) Set the table # for this table.
public void	startOptimizing(Optimizer optimizer, RowOrdering rowOrdering) Implements org.apache.derby.iapi.sql.compile.Optimizable.startOptimizing. Begin the optimization process for this Optimizable.
public boolean	supportsMultipleInstantiations() Implements org.apache.derby.iapi.sql.compile.Optimizable.supportsMultipleInstantiations. Tell whether this Optimizable can be instantiated multiple times
protected void	tellRowOrderingAboutConstantColumns(RowOrdering rowOrdering, OptimizablePredicateList predList) Tell the given RowOrdering about any columns that are constant due to their being equality comparisons with constant expressions.
public String	Returns: This object as a String toString() Overrides org.apache.derby.impl.sql.compile.ResultSetNode.toString. Convert this object to a String.
pack-priv FromTable	Returns: The new tree top (OuterJoin or InnerJoin). transformOuterJoins(ValueNode The predicate tree for the query block predicateTree, int numTables) Transform any Outer Join into an Inner Join where applicable.
public double	uniqueJoin(OptimizablePredicateList The predicate list to check predList) Implements org.apache.derby.iapi.sql.compile.Optimizable.uniqueJoin. Does this optimizable have a uniqueness condition on the given predicate list, and if so, how many unique keys will be returned per scan.
public void	updateBestPlanMap(short Indicates whether we're adding, loading, or removing a best plan for the OptimizerImpl/Optimizable. action, Object Object to use as the map key when adding/looking up a plan. If it is an instance of OptimizerImpl then it corresponds to an outer query; otherwise it's some Optimizable above this Optimizable that could potentially reject plans chosen by the OptimizerImpl to which this Optimizable belongs. planKey) Implements org.apache.derby.iapi.sql.compile.Optimizable.updateBestPlanMap. When remembering "truly the best" access path for an Optimizable, we have to keep track of which OptimizerImpl the "truly the best" access is for.
public void	verifyProperties(DataDictionary The DataDictionary to use. dDictionary) Implements org.apache.derby.iapi.sql.compile.Optimizable.verifyProperties. Verify that the Properties list with optimizer overrides, if specified, is valid

Inherited from org.apache.derby.impl.sql.compile.ResultSetNode:: addNewPredicate adjustForSortElimination adjustForSortElimination assignResultSetNumber bindExpressions bindExpressionsWithTables bindNonVTITables bindResultColumns bindResultColumns bindTargetExpressions bindUntypedNullsToResultColumns bindVTITables changeAccessPath columnTypesAndLengthsMatch considerMaterialization enhanceRCLForInsert ensurePredicateList flattenableInFromSubquery generateNormalizationResultSet generateResultSet genProjectRestrict genProjectRestrict genProjectRestrictForReordering getAllResultColumns getCandidateFinalCostEstimate getCostEstimate getCursorTargetTable getFromList getMatchingColumn getNewCostEstimate getOptimizer getOptimizerImpl getRCLForInsert getReferencedTableMap getResultColumns getResultSetNumber getScratchCostEstimate isCursorTargetTable isInsertSource isNotExists isOneRowResultSet isOrderedOn isPossibleDistinctScan isStatementResultSet isUpdatableCursor LOJgetReferencedTables makeResultDescription makeResultDescriptors markAsCursorTargetTable markForDistinctScan markStatementResultSet modifyAccessPaths modifyAccessPaths notCursorTargetTable notFlattenableJoin numDistinctAggregates optimize parseDefault performMaterialization preprocess printQueryExpressionSuffixClauses printSubNodes projectResultColumns pushOffsetFetchFirst pushOrderByList pushQueryExpressionSuffix referencesTarget rejectParameters rejectXMLValues renameGeneratedResultNames replaceOrForbidDefaults returnsAtMostOneRow setCandidateFinalCostEstimate setCostEstimate setCursorTargetTable setInsertSource setOptimizer setReferencedTableMap setResultColumns setResultSetNumber setResultToBooleanTrueNode setScratchCostEstimate setTableConstructorTypes subqueryReferencesTarget updateTargetLockMode verifySelectStarSubquery

pack-priv abstract Class FromTable

Field Summary

Constructor Summary

Method Summary