org.apache.derby.impl.sql.compile

Class BinaryListOperatorNode

java.lang.Object

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

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

org.apache.derby.impl.sql.compile.BinaryListOperatorNode

All Implemented Interfaces:

Node, Visitable

Direct Known Subclasses:

BetweenOperatorNode, InListOperatorNode

public abstract class BinaryListOperatorNode
extends ValueNode

A BinaryListOperatorNode represents a built-in "binary" operator with a single operand on the left of the operator and a list of operands on the right. This covers operators such as IN and BETWEEN.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) java.lang.String	leftInterfaceType
(package private) ValueNode	leftOperand
(package private) java.lang.String	methodName
(package private) java.lang.String	operator
(package private) ValueNode	receiver
(package private) java.lang.String	rightInterfaceType
(package private) ValueNodeList	rightOperandList

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

transformed

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
BinaryListOperatorNode()

Method Summary

Modifier and Type	Method and Description
(package private) void	acceptChildren(Visitor v) Accept the visitor for all visitable children of this node.
void	bindComparisonOperator() Test the type compatability of the operands and set the type info for this node.
ValueNode	bindExpression(FromList fromList, SubqueryList subqueryList, java.util.List aggregateVector) Bind this expression.
boolean	categorize(JBitSet referencedTabs, boolean simplePredsOnly) Categorize this predicate.
boolean	constantExpression(PredicateList whereClause) Return whether or not this expression tree represents a constant value.
ValueNode	getLeftOperand() Get the leftOperand
protected int	getOrderableVariantType() Return the variant type for the underlying expression.
ValueNodeList	getRightOperandList() Get the rightOperandList
void	init(java.lang.Object leftOperand, java.lang.Object rightOperandList, java.lang.Object operator, java.lang.Object methodName) Initializer for a BinaryListOperatorNode
boolean	isConstantExpression() Return whether or not this expression tree represents a constant expression.
protected boolean	isEquivalent(ValueNode o) Tests if this node is equivalent to the specified ValueNode.
ValueNode	preprocess(int numTables, FromList outerFromList, SubqueryList outerSubqueryList, PredicateList outerPredicateList) Preprocess an expression tree.
void	printSubNodes(int depth) Prints the sub-nodes of this object.
ValueNode	remapColumnReferencesToExpressions() Remap all ColumnReferences in this tree to be clones of the underlying expression.
void	setLeftOperand(ValueNode newLeftOperand) Set the leftOperand to the specified ValueNode
void	setRightOperandList(ValueNodeList newRightOperandList) Set the rightOperandList to the specified ValueNodeList
java.lang.String	toString() Convert this object to a String.

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

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

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, init, init, isAtomic, isInstanceOf, isPrivilegeCollectionRequired, isSessionSchema, isSessionSchema, makeConstantAction, makeTableName, makeTableName, nodeHeader, orReliability, parseStatement, printLabel, 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

methodName

java.lang.String methodName

operator

java.lang.String operator

leftInterfaceType

java.lang.String leftInterfaceType

rightInterfaceType

java.lang.String rightInterfaceType

receiver

ValueNode receiver

leftOperand

ValueNode leftOperand

rightOperandList

ValueNodeList rightOperandList

Constructor Detail

BinaryListOperatorNode

public BinaryListOperatorNode()

Method Detail

init

public void init(java.lang.Object leftOperand,
                 java.lang.Object rightOperandList,
                 java.lang.Object operator,
                 java.lang.Object methodName)

Initializer for a BinaryListOperatorNode

Specified by:

init in interface Node

Overrides:

init in class QueryTreeNode

Parameters:

leftOperand - The left operand of the node

rightOperandList - The right operand list of the node

operator - String representation of operator

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 ValueNode

Returns:

This object as a String

printSubNodes

public void printSubNodes(int depth)

Prints the sub-nodes of this object. See QueryTreeNode.java for how tree printing is supposed to work.

Overrides:

printSubNodes in class QueryTreeNode

Parameters:

depth - The depth of this node in the tree

bindExpression

public ValueNode bindExpression(FromList fromList,
                                SubqueryList subqueryList,
                                java.util.List aggregateVector)
                         throws StandardException

Bind this expression. This means binding the sub-expressions, as well as figuring out what the return type is for this expression.

Overrides:

bindExpression in class ValueNode

Parameters:

fromList - The FROM list for the query this expression is in, for binding columns.

subqueryList - The subquery list being built as we find SubqueryNodes

aggregateVector - The aggregate vector being built as we find AggregateNodes

Returns:

The new top of the expression tree.

Throws:

StandardException - Thrown on error

bindComparisonOperator

public void bindComparisonOperator()
                            throws StandardException

Test the type compatability of the operands and set the type info for this node. This method is useful both during binding and when we generate nodes within the language module outside of the parser.

Throws:

StandardException - Thrown on error

preprocess

public ValueNode preprocess(int numTables,
                            FromList outerFromList,
                            SubqueryList outerSubqueryList,
                            PredicateList outerPredicateList)
                     throws StandardException

Preprocess an expression tree. We do a number of transformations here (including subqueries, IN lists, LIKE and BETWEEN) plus subquery flattening. NOTE: This is done before the outer ResultSetNode is preprocessed.

Overrides:

preprocess in class ValueNode

Parameters:

numTables - Number of tables in the DML Statement

outerFromList - FromList from outer query block

outerSubqueryList - SubqueryList from outer query block

outerPredicateList - PredicateList from outer query block

Returns:

The modified expression

Throws:

StandardException - Thrown on error

setLeftOperand

public void setLeftOperand(ValueNode newLeftOperand)

Set the leftOperand to the specified ValueNode

Parameters:

newLeftOperand - The new leftOperand

getLeftOperand

public ValueNode getLeftOperand()

Get the leftOperand

Returns:

The current leftOperand.

setRightOperandList

public void setRightOperandList(ValueNodeList newRightOperandList)

Set the rightOperandList to the specified ValueNodeList

Parameters:

newRightOperandList - The new rightOperandList

getRightOperandList

public ValueNodeList getRightOperandList()

Get the rightOperandList

Returns:

The current rightOperandList.

categorize

public boolean categorize(JBitSet referencedTabs,
                          boolean simplePredsOnly)
                   throws StandardException

Categorize this predicate. Initially, this means building a bit map of the referenced tables for each predicate. If the source of this ColumnReference (at the next underlying level) is not a ColumnReference or a VirtualColumnNode then this predicate will not be pushed down. For example, in: select * from (select 1 from s) a (x) where x = 1 we will not push down x = 1. NOTE: It would be easy to handle the case of a constant, but if the inner SELECT returns an arbitrary expression, then we would have to copy that tree into the pushed predicate, and that tree could contain subqueries and method calls. RESOLVE - revisit this issue once we have views.

Overrides:

categorize in class ValueNode

Parameters:

referencedTabs - JBitSet with bit map of referenced FromTables

simplePredsOnly - Whether or not to consider method calls, field references and conditional nodes when building bit map

Returns:

boolean Whether or not source.expression is a ColumnReference or a VirtualColumnNode.

Throws:

StandardException - Thrown on error

remapColumnReferencesToExpressions

public ValueNode remapColumnReferencesToExpressions()
                                             throws StandardException

Remap all ColumnReferences in this tree to be clones of the underlying expression.

Overrides:

remapColumnReferencesToExpressions in class ValueNode

Returns:

ValueNode The remapped expression tree.

Throws:

StandardException - Thrown on error

isConstantExpression

public boolean isConstantExpression()

Return whether or not this expression tree represents a constant expression.

Overrides:

isConstantExpression in class ValueNode

Returns:

Whether or not this expression tree represents a constant expression.

constantExpression

public boolean constantExpression(PredicateList whereClause)

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 ValueNode

Returns:

True means this expression tree represents a constant value.

See Also:

ValueNode.constantExpression(org.apache.derby.impl.sql.compile.PredicateList)

getOrderableVariantType

protected int getOrderableVariantType()
                               throws StandardException

Return the variant type for the underlying expression. The variant type can be: VARIANT - variant within a scan (method calls and non-static field access) SCAN_INVARIANT - invariant within a scan (column references from outer tables) QUERY_INVARIANT - invariant within the life of a query CONSTANT - immutable

Overrides:

getOrderableVariantType in class ValueNode

Returns:

The variant type for the underlying expression.

Throws:

StandardException - thrown on error

acceptChildren

void acceptChildren(Visitor v)
             throws StandardException

Accept the visitor for all visitable children of this node.

Overrides:

acceptChildren in class QueryTreeNode

Parameters:

v - the visitor

Throws:

StandardException - on error

isEquivalent

protected boolean isEquivalent(ValueNode o)
                        throws StandardException

Description copied from class: ValueNode

Tests if this node is equivalent to the specified ValueNode. Two ValueNodes are considered equivalent if they will evaluate to the same value during query execution.

This method provides basic expression matching facility for the derived class of ValueNode and it is used by the language layer to compare the node structural form of the two expressions for equivalence at bind phase.

Note that it is not comparing the actual row values at runtime to produce a result; hence, when comparing SQL NULLs, they are considered to be equivalent and not unknown.

One usage case of this method in this context is to compare the select column expression against the group by expression to check if they are equivalent. e.g.:

SELECT c1+c2 FROM t1 GROUP BY c1+c2

In general, node equivalence is determined by the derived class of ValueNode. But they generally abide to the rules below:

• The two ValueNodes must be of the same node type to be considered equivalent. e.g.: CastNode vs. CastNode - equivalent (if their args also match), ColumnReference vs CastNode - not equivalent.
• If node P contains other ValueNode(s) and so on, those node(s) must also be of the same node type to be considered equivalent.
• If node P takes a parameter list, then the number of arguments and its arguments for the two nodes must also match to be considered equivalent. e.g.: CAST(c1 as INTEGER) vs CAST(c1 as SMALLINT), they are not equivalent.
• When comparing SQL NULLs in this context, they are considered to be equivalent.
• If this does not apply or it is determined that the two nodes are not equivalent then the derived class of this method should return false; otherwise, return true.

Specified by:

isEquivalent in class ValueNode

Parameters:

o - the node to compare this ValueNode against.

Returns:

true if the two nodes are equivalent, false otherwise.

Throws:

StandardException