LikeEscapeOperatorNode (Apache Derby V10.14 Internals)

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.TernaryOperatorNode
      - org.apache.derby.impl.sql.compile.LikeEscapeOperatorNode

All Implemented Interfaces:

Visitable
```
public final class LikeEscapeOperatorNode
extends TernaryOperatorNode
```
This node represents a like comparison operator (no escape) If the like pattern is a constant or a parameter then if possible the like is modified to include a >= and < operator. In some cases the like can be eliminated. By adding =, >= or < operators it may allow indexes to be used to greatly narrow the search range of the query, and allow optimizer to estimate number of rows to affected. constant or parameter LIKE pattern with prefix followed by optional wild card e.g. Derby% CHAR(n), VARCHAR(n) where n < 255 >= prefix padded with '' to length n -- e.g. Derby <= prefix appended with '' -- e.g. Derby [ can eliminate LIKE if constant. ] CHAR(n), VARCHAR(n), LONG VARCHAR where n >= 255 >= prefix backed up one characer <= prefix appended with '' no elimination of like parameter like pattern starts with wild card e.g. %Derby CHAR(n), VARCHAR(n) where n <= 256 >= '' padded with '' to length n <= '' no elimination of like CHAR(n), VARCHAR(n), LONG VARCHAR where n > 256 >= NULL <= '' Note that the Unicode value '' is defined as not a character value and can be used by a program for any purpose. We use it to set an upper bound on a character range with a less than predicate. We only need a single '' appended because the string 'Derby' is not a valid String because '' is not a valid character.

Field Summary

Fields
Modifier and Type Field Description

(package private) boolean addedEquals
Fields of the class

(package private) java.lang.String escape
- Fields inherited from class org.apache.derby.impl.sql.compile.QueryTreeNode
  AUTOINCREMENT_CREATE_MODIFY, AUTOINCREMENT_CYCLE, AUTOINCREMENT_INC_INDEX, AUTOINCREMENT_IS_AUTOINCREMENT_INDEX, AUTOINCREMENT_START_INDEX
- Fields inherited from class org.apache.derby.impl.sql.compile.TernaryOperatorNode
  K_LIKE, K_LOCATE, K_SUBSTRING, K_TIMESTAMPADD, K_TIMESTAMPDIFF, K_TRIM, kind, leftInterfaceType, leftOperand, methodName, operator, receiver, receiverInterfaceType, resultInterfaceType, rightInterfaceType, rightOperand, TernaryArgType, TernaryMethodNames, TernaryOperators, TernaryResultType, trimType
- Fields inherited from class org.apache.derby.impl.sql.compile.ValueNode
  transformed

Fields
Modifier and Type	Field	Description
`(package private) boolean`	`addedEquals`	Fields of the class
`(package private) java.lang.String`	`escape`

Constructor Summary

Constructors
Constructor	Description
`LikeEscapeOperatorNode(ValueNode receiver, ValueNode leftOperand, ValueNode rightOperand, ContextManager cm)`	Constructor for a LikeEscapeOperatorNode receiver like pattern [ escape escapeValue ]

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`bindComparisonOperator()`	Bind this operator
`(package private) ValueNode`	`bindExpression(FromList fromList, SubqueryList subqueryList, java.util.List<AggregateNode> aggregates)`	implement binding for like expressions.
`private void`	`finishBindExpr()`
`(package private) void`	`generateExpression(ExpressionClassBuilder acb, MethodBuilder mb)`	Do code generation for this binary operator.
`(package private) ValueNode`	`preprocess(int numTables, FromList outerFromList, SubqueryList outerSubqueryList, PredicateList outerPredicateList)`	Preprocess an expression tree.
`private ValueNode`	`setupOptimizeStringFromParameter(ValueNode parameterNode, ValueNode escapeNode, java.lang.String methodName, int maxWidth)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from class org.apache.derby.impl.sql.compile.OperatorNode
pushSqlXmlUtil

Methods inherited from class org.apache.derby.impl.sql.compile.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 org.apache.derby.impl.sql.compile.TernaryOperatorNode
acceptChildren, bindToBuiltIn, castArgToString, categorize, constantExpression, getLeftOperand, getReceiver, getRightOperand, isConstantExpression, isEquivalent, isSameNodeKind, locateBind, printSubNodes, remapColumnReferencesToExpressions, setLeftOperand, setRightOperand, substrBind, toString

Methods inherited from class org.apache.derby.impl.sql.compile.ValueNode
bindExpression, changeToCNF, checkIsBoolean, checkTopPredicatesForEqualsConditions, copyFields, eliminateNots, 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, optimizableEqualityNode, putAndsOnTop, requiresTypeFromContext, selectivity, setCollationInfo, setCollationInfo, setCollationUsingCompilationSchema, setCollationUsingCompilationSchema, setNullability, setTransformed, setType, setType, setType, updatableByCursor, verifyChangeToCNF, verifyEliminateNots, verifyPutAndsOnTop

- Field Detail
  - addedEquals
```
boolean addedEquals
```
    Fields of the class
  - escape
```
java.lang.String escape
```
- Constructor Detail
  - LikeEscapeOperatorNode
```
LikeEscapeOperatorNode(ValueNode receiver,
                       ValueNode leftOperand,
                       ValueNode rightOperand,
                       ContextManager cm)
```
    Constructor for a LikeEscapeOperatorNode receiver like pattern [ escape escapeValue ]
    
    Parameters:
    
    receiver - The left operand of the like: column, CharConstant or Parameter
    
    leftOperand - The right operand of the like: the pattern
    
    rightOperand - The optional escape clause, null if not present
    
    cm - The context manager
- Method Detail
  - bindExpression
```
ValueNode bindExpression(FromList fromList,
                         SubqueryList subqueryList,
                         java.util.List<AggregateNode> aggregates)
                  throws StandardException
```
    implement binding for like expressions.
    overrides BindOperatorNode.bindExpression because like has special requirements for parameter binding.
    
    Overrides:
    
    bindExpression in class TernaryOperatorNode
    
    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.
    
    Throws:
    
    StandardException - thrown on failure
  - finishBindExpr
```
private void finishBindExpr()
                     throws StandardException
```
    Throws:
    
    StandardException
  - bindComparisonOperator
```
public void bindComparisonOperator()
                            throws StandardException
```
    Bind this operator
    
    Throws:
    
    StandardException - Thrown on error
  - preprocess
```
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 TernaryOperatorNode
    
    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
  - generateExpression
```
void generateExpression(ExpressionClassBuilder acb,
                        MethodBuilder mb)
                 throws StandardException
```
    Do code generation for this binary operator. This code was copied from BinaryOperatorNode and stripped down
    
    Overrides:
    
    generateExpression in class TernaryOperatorNode
    
    Parameters:
    
    acb - The ExpressionClassBuilder for the class we're generating
    
    mb - The method the code to place the code
    
    Throws:
    
    StandardException - Thrown on error
  - setupOptimizeStringFromParameter
```
private ValueNode setupOptimizeStringFromParameter(ValueNode parameterNode,
                                                   ValueNode escapeNode,
                                                   java.lang.String methodName,
                                                   int maxWidth)
                                            throws StandardException
```
    Throws:
    
    StandardException

Class LikeEscapeOperatorNode

Field Summary

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

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

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

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

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

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

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

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

Field Detail

addedEquals

escape

Constructor Detail

LikeEscapeOperatorNode

Method Detail

bindExpression

finishBindExpr

bindComparisonOperator

preprocess

generateExpression

setupOptimizeStringFromParameter