Class UntypedNullConstantNode

java.lang.Object

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

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

org.apache.derby.impl.sql.compile.ConstantNode

org.apache.derby.impl.sql.compile.UntypedNullConstantNode

All Implemented Interfaces:

Visitable

public final class UntypedNullConstantNode
extends ConstantNode

An UntypedNullConstantNode represents a SQL NULL before it has been bound. The bind() operation will replace the UntypedNullConstantNodes with typed ConstantNodes.

Field Summary

Fields inherited from class ConstantNode

value

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
UntypedNullConstantNode(ContextManager cm)	Constructor for an UntypedNullConstantNode.

Method Summary

Modifier and Type	Method	Description
(package private) ValueNode	bindExpression(FromList fromList, SubqueryList subqueryList, List<AggregateNode> aggregates)	Bind this expression.
(package private) DataValueDescriptor	convertDefaultNode(DataTypeDescriptor typeDescriptor)	Translate a Default node into a default value, given a type descriptor.
(package private) void	generateConstant(ExpressionClassBuilder acb, MethodBuilder mb)	Should never be called for UntypedNullConstantNode because we shouldn't make it to generate

Methods inherited from class ConstantNode

constantExpression, generateExpression, getClone, getOrderableVariantType, getValue, isCloneable, isConstantExpression, isEquivalent, isNull, setValue, toString

Methods inherited from class ValueNode

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

Methods inherited from class QueryTreeNode

accept, acceptChildren, addTag, addUDTUsagePriv, addUDTUsagePriv, bindOffsetFetch, bindRowMultiSet, bindUserCatalogType, bindUserType, checkReliability, checkReliability, 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, printSubNodes, 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

Constructor Details

UntypedNullConstantNode

UntypedNullConstantNode(ContextManager cm)

Constructor for an UntypedNullConstantNode. Untyped constants contain no state (not too surprising).

Method Details

generateConstant

void generateConstant(ExpressionClassBuilder acb,
 MethodBuilder mb)

Should never be called for UntypedNullConstantNode because we shouldn't make it to generate

Specified by:

generateConstant in class ConstantNode

Parameters:

acb - The ExpressionClassBuilder for the class being built

mb - The method the expression will go into

convertDefaultNode

DataValueDescriptor convertDefaultNode(DataTypeDescriptor typeDescriptor)
                                throws StandardException

Translate a Default node into a default value, given a type descriptor.

Overrides:

convertDefaultNode in class QueryTreeNode

Parameters:

typeDescriptor - A description of the required data type.

Throws:

StandardException - Thrown on error

bindExpression

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

Description copied from class: ConstantNode

Bind this expression. This means binding the sub-expressions, as well as figuring out what the return type is for this expression. In this case, there are no sub-expressions, and the return type is already known, so this is just a stub.

Overrides:

bindExpression in class ConstantNode

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

aggregates - The aggregate list being built as we find AggregateNodes

Returns:

The new top of the expression tree.

See Also:

• ValueNode.bindExpression(FromList, SubqueryList, List)
• This does nothing-- the node is actually bound when bindUntypedNullsToResultColumns is called.