Class AggregateNode

java.lang.Object

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

org.apache.derby.impl.sql.compile.ValueNode

org.apache.derby.impl.sql.compile.OperatorNode

org.apache.derby.impl.sql.compile.UnaryOperatorNode

org.apache.derby.impl.sql.compile.AggregateNode

All Implemented Interfaces:

Visitable

class AggregateNode
extends UnaryOperatorNode

An Aggregate Node is a node that represents a set function/aggregate. It used for all system aggregates as well as user defined aggregates.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static final class	AggregateNode.BuiltinAggDescriptor

Field Summary

Fields

Modifier and Type	Field	Description
private Class<?>	aggregateDefinitionClass
private String	aggregateDefinitionClassName
private String	aggregateName
private StringBuffer	aggregatorClassName
private static AggregateNode.BuiltinAggDescriptor[]	BUILTIN_MODERN_AGGS
private ClassInspector	classInspector
private boolean	distinct
private ResultColumn	generatedRC
private ColumnReference	generatedRef
private AggregateDefinition	uad
private TableName	userAggregateName

Fields inherited from class UnaryOperatorNode

K_BASE, K_XMLPARSE, K_XMLSERIALIZE, kind, methodName, operand, operator, receiverInterfaceType, resultInterfaceType, UnaryArgTypes, UnaryMethodNames, UnaryOperators, UnaryResultTypes

Fields inherited from class ValueNode

transformed

Fields inherited from class QueryTreeNode

AUTOINCREMENT_CREATE_MODIFY, AUTOINCREMENT_CYCLE, AUTOINCREMENT_INC_INDEX, AUTOINCREMENT_IS_AUTOINCREMENT_INDEX, AUTOINCREMENT_START_INDEX

Constructor Summary

Constructors

Constructor	Description
AggregateNode(ValueNode operand, Class<?> uadClass, boolean distinct, String aggregateName, ContextManager cm)
AggregateNode(ValueNode operand, TableName uadClass, boolean distinct, String aggregateName, ContextManager cm)
AggregateNode(ValueNode operand, UserAggregateDefinition uadClass, TableName alias, boolean distinct, String aggregateName, ContextManager cm)	Constructed when binding a StaticMethodNode that we realize is an aggregate.

Method Summary

Modifier and Type	Method	Description
(package private) void	acceptChildren(Visitor v)	Accept the visitor for all visitable children of this node.
(package private) ValueNode	bindExpression(FromList fromList, SubqueryList subqueryList, List<AggregateNode> aggregates)	Bind this operator.
private void	checkAggregatorClassName(String className)
(package private) boolean	constantExpression(PredicateList where)	Return whether or not this expression tree represents a constant value.
(package private) void	generateExpression(ExpressionClassBuilder acb, MethodBuilder mb)	Do code generation for this unary operator.
(package private) AggregateDefinition	getAggregateDefinition()	Get the AggregateDefinition.
(package private) String	getAggregateName()	Get the class that implements that aggregator for this node.
(package private) String	getAggregatorClassName()	Get the class that implements that aggregator for this node.
(package private) ResultColumn	getGeneratedRC()	Get the generated ResultColumn where this aggregate now resides after a call to replaceAggregatesWithColumnReference().
(package private) ColumnReference	getGeneratedRef()	Get the generated ColumnReference to this aggregate after the parent called replaceAggregatesWithColumnReference().
(package private) ResultColumn	getNewAggregatorResultColumn(DataDictionary dd)	Get the result column that has a new aggregator.
(package private) ResultColumn	getNewExpressionResultColumn(DataDictionary dd)	Get the aggregate expression in a new result column.
(package private) ValueNode	getNewNullResultExpression()	Get the null aggregate result expression column.
String	getSQLName()	Get the SQL name of the aggregate
private void	instantiateAggDef()
(package private) boolean	isConstant()
(package private) boolean	isDistinct()	Indicate whether this aggregate is distinct or not.
private boolean	isUserDefinedAggregate()	Return true if this is a user-defined aggregate
(package private) ValueNode	replaceAggregatesWithColumnReferences(ResultColumnList rcl, int tableNumber)	Replace aggregates in the expression tree with a ColumnReference to that aggregate, append the aggregate to the supplied RCL (assumed to be from the child ResultSetNode) and return the ColumnReference.
(package private) static AliasDescriptor	resolveAggregate(DataDictionary dd, SchemaDescriptor sd, String rawName, boolean noSchema)	Resolve a user-defined aggregate.
private static AliasDescriptor	resolveBuiltinAggregate(DataDictionary dd, String rawName, boolean noSchema)	Construct an AliasDescriptor for a modern builtin aggregate.
private void	setUserDefinedAggregate(UserAggregateDefinition userAgg)	initialize fields for user defined aggregate
String	toString()	Print a string ref of this node.

Methods inherited from class UnaryOperatorNode

addXmlOpMethodParams, bindOperand, bindParameter, categorize, getOperand, getOperatorString, getOrderableVariantType, getParameterOperand, getReceiverInterfaceName, isConstantExpression, isEquivalent, isSameNodeKind, preprocess, printSubNodes, remapColumnReferencesToExpressions, setMethodName, setOperator

Methods inherited from class OperatorNode

pushSqlXmlUtil

Methods inherited from class ValueNode

bindExpression, changeToCNF, checkIsBoolean, checkTopPredicatesForEqualsConditions, copyFields, eliminateNots, evaluateConstantExpressions, genEqualsFalseTree, generate, genIsNullTree, genSQLJavaSQLTree, getClone, getColumnName, getConstantValueAsObject, getDataValueFactory, getSchemaName, getSourceResultColumn, getTableName, getTablesReferenced, getTransformed, getTypeCompiler, getTypeId, getTypeServices, isBinaryEqualsOperatorNode, isBooleanFalse, isBooleanTrue, isCloneable, isInListProbeNode, isParameterNode, isRelationalOperator, optimizableEqualityNode, putAndsOnTop, requiresTypeFromContext, selectivity, setCollationInfo, setCollationInfo, setCollationUsingCompilationSchema, setCollationUsingCompilationSchema, setNullability, setTransformed, setType, setType, setType, updatableByCursor, verifyChangeToCNF, verifyEliminateNots, verifyPutAndsOnTop

Methods inherited from class QueryTreeNode

accept, addTag, addUDTUsagePriv, addUDTUsagePriv, bindOffsetFetch, bindRowMultiSet, bindUserCatalogType, bindUserType, checkReliability, checkReliability, convertDefaultNode, copyTagsFrom, createTypeDependency, debugFlush, debugPrint, disablePrivilegeCollection, formatNodeString, generateAuthorizeCheck, getBeginOffset, getClassFactory, getCompilerContext, getContext, getContextManager, getDataDictionary, getDependencyManager, getEndOffset, getExecutionFactory, getGenericConstantActionFactory, getIntProperty, getLanguageConnectionContext, getLongProperty, getNullNode, getOffsetOrderedNodes, getOptimizerFactory, getOptimizerTracer, getParameterTypes, getSchemaDescriptor, getSchemaDescriptor, getStatementType, getTableDescriptor, getTypeCompiler, getUDTDesc, isAtomic, isPrivilegeCollectionRequired, isSessionSchema, isSessionSchema, makeConstantAction, makeTableName, makeTableName, nodeHeader, optimizerTracingIsOn, orReliability, parseSearchCondition, parseStatement, printLabel, referencesSessionSchema, resolveTableToSynonym, setBeginOffset, setEndOffset, setRefActionInfo, stackPrint, taggedWith, treePrint, treePrint, verifyClassExist

Methods inherited from class Object

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

Field Details

BUILTIN_MODERN_AGGS

private static AggregateNode.BuiltinAggDescriptor[] BUILTIN_MODERN_AGGS

distinct

private boolean distinct

uad

private AggregateDefinition uad

userAggregateName

private TableName userAggregateName

aggregatorClassName

private StringBuffer aggregatorClassName

aggregateDefinitionClassName

private String aggregateDefinitionClassName

aggregateDefinitionClass

private Class<?> aggregateDefinitionClass

classInspector

private ClassInspector classInspector

aggregateName

private String aggregateName

generatedRC

private ResultColumn generatedRC

generatedRef

private ColumnReference generatedRef

Constructor Details

AggregateNode

AggregateNode(ValueNode operand,
 UserAggregateDefinition uadClass,
 TableName alias,
 boolean distinct,
 String aggregateName,
 ContextManager cm)
       throws StandardException

Constructed when binding a StaticMethodNode that we realize is an aggregate.

Parameters:

operand - the value expression for the aggregate

uadClass - the class of the user aggregate definition

alias - the name by which the aggregate was called

distinct - boolean indicating whether this is distinct or not.

aggregateName - the name of the aggregate from the user's perspective, e.g. MAX

cm - context manager

Throws:

StandardException

AggregateNode

AggregateNode(ValueNode operand,
 TableName uadClass,
 boolean distinct,
 String aggregateName,
 ContextManager cm)
       throws StandardException

Parameters:

operand - the value expression for the aggregate

uadClass - the class name for user aggregate definition for the aggregate

distinct - boolean indicating whether this is distinct or not.

aggregateName - the name of the aggregate from the user's perspective, e.g. MAX

cm - context manager

Throws:

StandardException

AggregateNode

AggregateNode(ValueNode operand,
 Class<?> uadClass,
 boolean distinct,
 String aggregateName,
 ContextManager cm)
       throws StandardException

Parameters:

operand - the value expression for the aggregate

uadClass - Class for the internal aggregate type

distinct - boolean indicating whether this is distinct or not.

aggregateName - the name of the aggregate from the user's perspective, e.g. MAX

cm - context manager

Throws:

StandardException

Method Details

setUserDefinedAggregate

private void setUserDefinedAggregate(UserAggregateDefinition userAgg)

initialize fields for user defined aggregate

replaceAggregatesWithColumnReferences

ValueNode replaceAggregatesWithColumnReferences(ResultColumnList rcl,
 int tableNumber)
                                         throws StandardException

Replace aggregates in the expression tree with a ColumnReference to that aggregate, append the aggregate to the supplied RCL (assumed to be from the child ResultSetNode) and return the ColumnReference. This is useful for pushing aggregates in the Having clause down to the user's select at parse time. It is also used for moving around Aggregates in the select list when creating the Group By node. In that case it is called after bind time, so we need to create the column differently.

Parameters:

rcl - The RCL to append to.

tableNumber - The tableNumber for the new ColumnReference

Returns:

ValueNode The (potentially) modified tree.

Throws:

StandardException - Thrown on error

getAggregateDefinition

AggregateDefinition getAggregateDefinition()

Get the AggregateDefinition.

Returns:

The AggregateDefinition

getGeneratedRC

ResultColumn getGeneratedRC()

Get the generated ResultColumn where this aggregate now resides after a call to replaceAggregatesWithColumnReference().

Returns:

the result column

getGeneratedRef

ColumnReference getGeneratedRef()

Get the generated ColumnReference to this aggregate after the parent called replaceAggregatesWithColumnReference().

Returns:

the column reference

bindExpression

ValueNode bindExpression(FromList fromList,
 SubqueryList subqueryList,
 List<AggregateNode> aggregates)
                  throws StandardException

Bind this operator. Determine the type of the subexpression, and pass that into the UserAggregate.

Overrides:

bindExpression in class UnaryOperatorNode

Parameters:

fromList - The query's FROM list

subqueryList - The subquery list being built as we find SubqueryNodes

aggregates - The aggregate list being built as we find AggregateNodes

Returns:

The new top of the expression tree.

Throws:

StandardException - Thrown on error

resolveAggregate

static AliasDescriptor resolveAggregate(DataDictionary dd,
 SchemaDescriptor sd,
 String rawName,
 boolean noSchema)
                                 throws StandardException

Resolve a user-defined aggregate.

Throws:

StandardException

resolveBuiltinAggregate

private static AliasDescriptor resolveBuiltinAggregate(DataDictionary dd,
 String rawName,
 boolean noSchema)
                                                throws StandardException

Construct an AliasDescriptor for a modern builtin aggregate.

Throws:

StandardException

checkAggregatorClassName

private void checkAggregatorClassName(String className)
                               throws StandardException

Throws:

StandardException

instantiateAggDef

private void instantiateAggDef()
                        throws StandardException

Throws:

StandardException

isDistinct

boolean isDistinct()

Indicate whether this aggregate is distinct or not.

Returns:

true/false

getAggregatorClassName

String getAggregatorClassName()

Get the class that implements that aggregator for this node.

Returns:

the class name

getAggregateName

String getAggregateName()

Get the class that implements that aggregator for this node.

Returns:

the class name

getNewAggregatorResultColumn

ResultColumn getNewAggregatorResultColumn(DataDictionary dd)
                                   throws StandardException

Get the result column that has a new aggregator. This aggregator will be fed into the sorter.

Parameters:

dd - the data dictionary

Returns:

the result column. WARNING: it still needs to be bound

Throws:

StandardException - on error

getNewExpressionResultColumn

ResultColumn getNewExpressionResultColumn(DataDictionary dd)
                                   throws StandardException

Get the aggregate expression in a new result column.

Parameters:

dd - the data dictionary

Returns:

the result column. WARNING: it still needs to be bound

Throws:

StandardException - on error

getNewNullResultExpression

ValueNode getNewNullResultExpression()
                              throws StandardException

Get the null aggregate result expression column.

Returns:

the value node

Throws:

StandardException - on error

generateExpression

void generateExpression(ExpressionClassBuilder acb,
 MethodBuilder mb)
                 throws StandardException

Do code generation for this unary operator. Should never be called for an aggregate -- it should be converted into something else by code generation time.

Overrides:

generateExpression in class UnaryOperatorNode

Parameters:

acb - The ExpressionClassBuilder for the class we're generating

mb - The method the code to place the code

Throws:

StandardException - Thrown on error

toString

public String toString()

Print a string ref of this node.

Overrides:

toString in class UnaryOperatorNode

Returns:

a string representation of this node

isConstant

boolean isConstant()

constantExpression

boolean constantExpression(PredicateList where)

Description copied from class: ValueNode

Return whether or not this expression tree represents a constant value. In this case, "constant" means that it will always evaluate to the same thing, even if it includes columns. A column is constant if it is compared to a constant expression.

Overrides:

constantExpression in class UnaryOperatorNode

Returns:

True means this expression tree represents a constant value.

See Also:

• ValueNode.constantExpression(PredicateList)

getSQLName

public String getSQLName()

Get the SQL name of the aggregate

isUserDefinedAggregate

private boolean isUserDefinedAggregate()

Return true if this is a user-defined aggregate

acceptChildren

void acceptChildren(Visitor v)
             throws StandardException

Description copied from class: UnaryOperatorNode

Accept the visitor for all visitable children of this node.

Overrides:

acceptChildren in class UnaryOperatorNode

Parameters:

v - the visitor

Throws:

StandardException - on error