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

java.lang.Object
  extended by org.apache.derby.impl.sql.compile.QueryTreeNode
      extended by org.apache.derby.impl.sql.compile.ValueNode
          extended by org.apache.derby.impl.sql.compile.UnaryOperatorNode
All Implemented Interfaces:
Visitable
Direct Known Subclasses:
AggregateNode, DB2LengthOperatorNode, ExtractOperatorNode, LengthOperatorNode, SimpleStringOperatorNode, UnaryArithmeticOperatorNode, UnaryComparisonOperatorNode, UnaryDateTimestampOperatorNode, UnaryLogicalOperatorNode, WindowFunctionNode

public class UnaryOperatorNode
extends ValueNode

A UnaryOperatorNode represents a built-in unary operator as defined by the ANSI/ISO SQL standard. This covers operators like +, -, NOT, and IS NULL. Java operators are not represented here: the JSQL language allows Java methods to be called from expressions, but not Java operators.


Field Summary
private  java.lang.Object[] additionalArgs
           
(package private)  java.lang.String methodName
           
(package private)  ValueNode operand
          WARNING: operand may be NULL for COUNT(*).
(package private)  java.lang.String operator
           
private  int operatorType
          Operator type, only valid for XMLPARSE and XMLSERIALIZE.
(package private)  java.lang.String receiverInterfaceType
           
(package private)  java.lang.String resultInterfaceType
           
private  SqlXmlUtil sqlxUtil
           
(package private) static java.lang.String[] UnaryArgTypes
           
(package private) static java.lang.String[] UnaryMethodNames
           
(package private) static java.lang.String[] UnaryOperators
           
(package private) static java.lang.String[] UnaryResultTypes
           
static int XMLPARSE_OP
           
static int XMLSERIALIZE_OP
           
 
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, isPrivilegeCollectionRequired
 
Constructor Summary
UnaryOperatorNode()
           
 
Method Summary
(package private)  void acceptChildren(Visitor v)
          Accept the visitor for all visitable children of this node.
protected  int addXmlOpMethodParams(ExpressionClassBuilder acb, MethodBuilder mb)
          Add some additional arguments to our method call for XML related operations like XMLPARSE and XMLSERIALIZE.
 ValueNode bindExpression(FromList fromList, SubqueryList subqueryList, java.util.Vector aggregateVector)
          Bind this expression.
protected  void bindOperand(FromList fromList, SubqueryList subqueryList, java.util.Vector aggregateVector)
          Bind the operand for this unary operator.
(package private)  void bindParameter()
          By default unary operators don't accept ?
private  void bindXMLParse()
          Bind an XMLPARSE operator.
private  void bindXMLSerialize()
          Bind an XMLSERIALIZE operator.
 boolean categorize(JBitSet referencedTabs, boolean simplePredsOnly)
          Categorize this predicate.
 boolean constantExpression(PredicateList whereClause)
          Return whether or not this expression tree represents a constant value.
 void generateExpression(ExpressionClassBuilder acb, MethodBuilder mb)
          Do code generation for this unary operator.
 ValueNode getOperand()
          Get the operand of this unary operator.
(package private)  java.lang.String getOperatorString()
          Get the operator of this unary operator.
protected  int getOrderableVariantType()
          Return the variant type for the underlying expression.
 ParameterNode getParameterOperand()
          Get the parameter operand of this unary operator.
 java.lang.String getReceiverInterfaceName()
          Determine the type the binary method is called on.
 void init(java.lang.Object operand)
          Initializer for a UnaryOperatorNode
 void init(java.lang.Object operand, java.lang.Object operatorOrOpType, java.lang.Object methodNameOrAddedArgs)
          Initializer for a UnaryOperatorNode.
 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.
(package private)  void setMethodName(java.lang.String methodName)
          Set the methodName.
(package private)  void setOperator(java.lang.String operator)
          Set the operator.
 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, 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, 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, getRowEstimate, getSchemaDescriptor, getSchemaDescriptor, getStatementType, getTableDescriptor, getTypeCompiler, 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

operator

java.lang.String operator

methodName

java.lang.String methodName

operatorType

private int operatorType
Operator type, only valid for XMLPARSE and XMLSERIALIZE.


resultInterfaceType

java.lang.String resultInterfaceType

receiverInterfaceType

java.lang.String receiverInterfaceType

operand

ValueNode operand
WARNING: operand may be NULL for COUNT(*).


XMLPARSE_OP

public static final int XMLPARSE_OP
See Also:
Constant Field Values

XMLSERIALIZE_OP

public static final int XMLSERIALIZE_OP
See Also:
Constant Field Values

UnaryOperators

static final java.lang.String[] UnaryOperators

UnaryMethodNames

static final java.lang.String[] UnaryMethodNames

UnaryResultTypes

static final java.lang.String[] UnaryResultTypes

UnaryArgTypes

static final java.lang.String[] UnaryArgTypes

additionalArgs

private java.lang.Object[] additionalArgs

sqlxUtil

private SqlXmlUtil sqlxUtil
Constructor Detail

UnaryOperatorNode

public UnaryOperatorNode()
Method Detail

init

public void init(java.lang.Object operand,
                 java.lang.Object operatorOrOpType,
                 java.lang.Object methodNameOrAddedArgs)
Initializer for a UnaryOperatorNode.

init

public void init(java.lang.Object operand)
Initializer for a UnaryOperatorNode

Overrides:
init in class QueryTreeNode
Parameters:
operand - The operand of the node

setOperator

void setOperator(java.lang.String operator)
Set the operator.

Parameters:
operator - The operator.

getOperatorString

java.lang.String getOperatorString()
Get the operator of this unary operator.

Returns:
The operator of this unary operator.

setMethodName

void setMethodName(java.lang.String methodName)
Set the methodName.

Parameters:
methodName - The methodName.

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

getOperand

public ValueNode getOperand()
Get the operand of this unary operator.

Returns:
The operand of this unary operator.

getParameterOperand

public ParameterNode getParameterOperand()
                                  throws StandardException
Get the parameter operand of this unary operator. For the example below, for abs unary operator node, we want to get ? select * from t1 where -? = max_cni(abs(-?), sqrt(+?)) This gets called when ParameterNode is needed to get parameter specific information like getDefaultValue(), getParameterNumber() etc

Returns:
The parameter operand of this unary operator else null.
Throws:
StandardException

bindExpression

public ValueNode bindExpression(FromList fromList,
                                SubqueryList subqueryList,
                                java.util.Vector 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. This method is the implementation for XMLPARSE and XMLSERIALIZE. Sub-classes need to implement their own bindExpression() method for their own specific rules.

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

bindOperand

protected void bindOperand(FromList fromList,
                           SubqueryList subqueryList,
                           java.util.Vector aggregateVector)
                    throws StandardException
Bind the operand for this unary operator. Binding the operator may change the operand node. Sub-classes bindExpression() methods need to call this method to bind the operand.

Throws:
StandardException

bindXMLParse

private void bindXMLParse()
                   throws StandardException
Bind an XMLPARSE operator. Makes sure the operand type is correct, and sets the result type.

Throws:
StandardException - Thrown on error

bindXMLSerialize

private void bindXMLSerialize()
                       throws StandardException
Bind an XMLSERIALIZE operator. Makes sure the operand type and target type are both correct, and sets the result type.

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

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)

bindParameter

void bindParameter()
             throws StandardException
By default unary operators don't accept ? parameters as operands. This can be over-ridden for particular unary operators. We throw an exception if the parameter doesn't have a datatype assigned to it yet.

Throws:
StandardException - Thrown if ? parameter doesn't have a type bound to it yet. ? parameter where it isn't allowed.

generateExpression

public void generateExpression(ExpressionClassBuilder acb,
                               MethodBuilder mb)
                        throws StandardException
Do code generation for this unary operator.

Overrides:
generateExpression in class ValueNode
Parameters:
acb - The ExpressionClassBuilder for the class we're generating
mb - The method the expression will go into
Throws:
StandardException - Thrown on error

getReceiverInterfaceName

public java.lang.String getReceiverInterfaceName()
                                          throws StandardException
Determine the type the binary method is called on. By default, based on the receiver. Override in nodes that use methods on super-interfaces of the receiver's interface, such as comparisons.

Throws:
StandardException - Thrown on error

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 expressions) 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

addXmlOpMethodParams

protected int addXmlOpMethodParams(ExpressionClassBuilder acb,
                                   MethodBuilder mb)
                            throws StandardException
Add some additional arguments to our method call for XML related operations like XMLPARSE and XMLSERIALIZE.

Parameters:
mb - The MethodBuilder that will make the call.
Returns:
Number of parameters added.
Throws:
StandardException

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:

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

Built on Thu 2010-12-23 20:49:13+0000, from revision ???

Apache Derby V10.6 Internals - Copyright © 2004,2007 The Apache Software Foundation. All Rights Reserved.