class ConditionalNode extends ValueNode
Modifier and Type | Class and Description |
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private class |
ConditionalNode.ReplaceCaseOperandVisitor
A visitor that replaces all occurrences of the
caseOperand node
in a tree with dummy parameter nodes. |
Modifier and Type | Field and Description |
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private CachedValueNode |
caseOperand
The case operand if this is a simple case expression.
|
private ValueNodeList |
testConditions
The list of test conditions in the WHEN clauses.
|
private ValueNodeList |
thenElseList
The list of corresponding THEN expressions to the test conditions in
testConditions . |
transformed
AUTOINCREMENT_CREATE_MODIFY, AUTOINCREMENT_CYCLE, AUTOINCREMENT_INC_INDEX, AUTOINCREMENT_IS_AUTOINCREMENT_INDEX, AUTOINCREMENT_START_INDEX
Constructor and Description |
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ConditionalNode(CachedValueNode caseOperand,
ValueNodeList testConditions,
ValueNodeList thenElseList,
ContextManager cm)
Constructor for a ConditionalNode
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Modifier and Type | Method and Description |
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(package private) void |
acceptChildren(Visitor v)
Accept the visitor for all visitable children of this node.
|
private ValueNodeList |
bindCaseOperand(CompilerContext cc,
FromList fromList,
SubqueryList subqueryList,
java.util.List<AggregateNode> aggregates)
Bind the case operand, if there is one, and check that it doesn't
contain anything that's illegal in a case operand (such as calls to
routines that are non-deterministic or modify SQL).
|
(package private) ValueNode |
bindExpression(FromList fromList,
SubqueryList subqueryList,
java.util.List<AggregateNode> aggregates)
Bind this expression.
|
(package private) boolean |
categorize(JBitSet referencedTabs,
boolean simplePredsOnly)
Categorize this predicate.
|
(package private) boolean |
constantExpression(PredicateList whereClause)
Return whether or not this expression tree represents a constant value.
|
(package private) ValueNode |
eliminateNots(boolean underNotNode)
Eliminate NotNodes in the current query block.
|
(package private) void |
generateExpression(ExpressionClassBuilder acb,
MethodBuilder mb)
Do code generation for this conditional expression.
|
(package private) boolean |
isConstantExpression()
Return whether or not this expression tree represents a constant expression.
|
(package private) boolean |
isEquivalent(ValueNode o)
Tests if this node is equivalent to the specified ValueNode.
|
(package private) ValueNode |
preprocess(int numTables,
FromList outerFromList,
SubqueryList outerSubqueryList,
PredicateList outerPredicateList)
Preprocess an expression tree.
|
(package private) void |
printSubNodes(int depth)
Prints the sub-nodes of this object.
|
private void |
recastNullNodes(DataTypeDescriptor castType,
FromList fromList,
SubqueryList subqueryList,
java.util.List<AggregateNode> aggregates)
This method makes sure any SQL NULLs will be cast to the correct type.
|
(package private) ValueNode |
remapColumnReferencesToExpressions()
Remap all ColumnReferences in this tree to be clones of the
underlying expression.
|
bindExpression, changeToCNF, checkIsBoolean, checkTopPredicatesForEqualsConditions, copyFields, evaluateConstantExpressions, genEqualsFalseTree, generate, genIsNullTree, genSQLJavaSQLTree, getClone, getColumnName, getConstantValueAsObject, getDataValueFactory, getOrderableVariantType, getSchemaName, getSourceResultColumn, getTableName, getTablesReferenced, getTransformed, getTypeCompiler, getTypeId, getTypeServices, isBinaryEqualsOperatorNode, isBooleanFalse, isBooleanTrue, isCloneable, isInListProbeNode, isParameterNode, isRelationalOperator, isSameNodeKind, optimizableEqualityNode, putAndsOnTop, requiresTypeFromContext, selectivity, setCollationInfo, setCollationInfo, setCollationUsingCompilationSchema, setCollationUsingCompilationSchema, setNullability, setTransformed, setType, setType, setType, toString, updatableByCursor, verifyChangeToCNF, verifyEliminateNots, verifyPutAndsOnTop
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
private CachedValueNode caseOperand
null
.private ValueNodeList testConditions
private ValueNodeList thenElseList
testConditions
. The last element represents the ELSE clause.ConditionalNode(CachedValueNode caseOperand, ValueNodeList testConditions, ValueNodeList thenElseList, ContextManager cm)
caseOperand
- The case operand if this is a simple case
expression, or null
otherwisetestConditions
- The boolean test conditionsthenElseList
- ValueNodeList with then and else expressionscm
- The context managervoid printSubNodes(int depth)
printSubNodes
in class QueryTreeNode
depth
- The depth of this node in the treeprivate void recastNullNodes(DataTypeDescriptor castType, FromList fromList, SubqueryList subqueryList, java.util.List<AggregateNode> aggregates) throws StandardException
castType
- The type to cast SQL parsed NULL's too.fromList
- FromList to pass on to bindExpression if recast is performedsubqueryList
- SubqueryList to pass on to bindExpression if recast is performedaggregates
- List of aggregates to pass on to bindExpression if recast is performedStandardException
- Thrown on error.ValueNode bindExpression(FromList fromList, SubqueryList subqueryList, java.util.List<AggregateNode> aggregates) throws StandardException
bindExpression
in class ValueNode
fromList
- The FROM list for the query this
expression is in, for binding columns.subqueryList
- The subquery list being built as we find SubqueryNodesaggregates
- The aggregate list being built as we find AggregateNodesStandardException
- Thrown on errorprivate ValueNodeList bindCaseOperand(CompilerContext cc, FromList fromList, SubqueryList subqueryList, java.util.List<AggregateNode> aggregates) throws StandardException
Bind the case operand, if there is one, and check that it doesn't contain anything that's illegal in a case operand (such as calls to routines that are non-deterministic or modify SQL).
Also, if the type of the case operand needs to be inferred, insert
dummy parameter nodes into testConditions
instead of the
case operand, so that the type can be inferred individually for each
test condition. Later, bindExpression(org.apache.derby.impl.sql.compile.FromList, org.apache.derby.impl.sql.compile.SubqueryList, java.util.List<org.apache.derby.impl.sql.compile.AggregateNode>)
will find a common
type for all of them, use that type for the case operand, and reinsert
the case operand into the test conditions.
null
is returnedStandardException
ValueNode preprocess(int numTables, FromList outerFromList, SubqueryList outerSubqueryList, PredicateList outerPredicateList) throws StandardException
preprocess
in class ValueNode
numTables
- Number of tables in the DML StatementouterFromList
- FromList from outer query blockouterSubqueryList
- SubqueryList from outer query blockouterPredicateList
- PredicateList from outer query blockStandardException
- Thrown on errorboolean categorize(JBitSet referencedTabs, boolean simplePredsOnly) throws StandardException
categorize
in class ValueNode
referencedTabs
- JBitSet with bit map of referenced FromTablessimplePredsOnly
- Whether or not to consider method
calls, field references and conditional nodes
when building bit mapStandardException
- Thrown on errorValueNode remapColumnReferencesToExpressions() throws StandardException
remapColumnReferencesToExpressions
in class ValueNode
StandardException
- Thrown on errorboolean isConstantExpression()
isConstantExpression
in class ValueNode
boolean constantExpression(PredicateList whereClause)
ValueNode
constantExpression
in class ValueNode
ValueNode.constantExpression(org.apache.derby.impl.sql.compile.PredicateList)
ValueNode eliminateNots(boolean underNotNode) throws StandardException
eliminateNots
in class ValueNode
underNotNode
- Whether or not we are under a NotNode.StandardException
- Thrown on errorvoid generateExpression(ExpressionClassBuilder acb, MethodBuilder mb) throws StandardException
generateExpression
in class ValueNode
acb
- The ExpressionClassBuilder for the class we're generatingmb
- The method the expression will go intoStandardException
- Thrown on errorvoid acceptChildren(Visitor v) throws StandardException
acceptChildren
in class QueryTreeNode
v
- the visitorStandardException
- on errorboolean isEquivalent(ValueNode o) throws StandardException
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:
isEquivalent
in class ValueNode
o
- the node to compare this ValueNode against.true
if the two nodes are equivalent,
false
otherwise.StandardException
Apache Derby V10.13 Internals - Copyright © 2004,2016 The Apache Software Foundation. All Rights Reserved.