edu.udo.cs.miningmart.operator
Class JoinByKey

java.lang.Object
  edu.udo.cs.miningmart.operator.ExecutableOperator
      edu.udo.cs.miningmart.operator.ConceptOperator
          edu.udo.cs.miningmart.operator.SingleCSOperator
              edu.udo.cs.miningmart.operator.JoinByKey

public class JoinByKey

extends SingleCSOperator

This operator joins several concepts using their specified keys. The output is one concept.

Version:

$Id: JoinByKey.java,v 1.4 2006/04/11 14:10:12 euler Exp $

Author:

Timm Euler

Field Summary

Fields inherited from class edu.udo.cs.miningmart.operator.ExecutableOperator

generatedSQLDefinitions

Constructor Summary

JoinByKey()

Method Summary

protected java.lang.String	createMetadataForOneBA(BaseAttribute inBA, BaseAttribute outBA, Columnset csForOutputConcept, java.lang.String columnExpr) Overrides the superclass method because here a mapping is used.
protected java.lang.String	generateColumns(Columnset csForOutputConcept) This method is overridden because the copying of columns from input to output concept works differently for this operator.
java.lang.String	generateSQLDefinition(java.lang.String selectPart) This method must return the SQL definition of the newly created ColumnSet.
protected Feature[][]	getInOutMap() Getter method for the mapping parameters.
Concept	getInputConcept() This method overrides the superclass method, so that it can still be used, although this operator has more than one input concept.
protected Concept[]	getSortedConcepts() Gets the parameters "TheConcepts".
protected BaseAttribute[]	getSortedKeys() Gets the primary keys of TheConcepts.
java.lang.String	getTypeOfNewColumnSet() This method must return the entry String for the M4 table "Columnset_t", indicating whether the new Columnset is a view or a table.
void	load(Step st) Loads all parameters for this operator.
protected boolean	mustCopyFeature(java.lang.String nameOfFeature) This method is for operators that do not copy all Features of the input concept to the output concept.
protected void	setNewCSMultiStepBranch(Columnset newCS, int index) MultiStepBranch information of all Concepts need to be merged.

Methods inherited from class edu.udo.cs.miningmart.operator.SingleCSOperator

generateColumnSetsForOp, generateSQLDefinition, getNewCSName, getTypeOfNewColumnSet

Methods inherited from class edu.udo.cs.miningmart.operator.ConceptOperator

compileStatement, createMetadata, createSingleColumnSet, createStatement, estimateStatistics, getNewCSName, getOutputConcept, getStringForSelection

Methods inherited from class edu.udo.cs.miningmart.operator.ExecutableOperator

autoPrint, checkConditions, doPrint, doPrint, execute, executeBusinessSingleValueSqlRead, executeBusinessSingleValueSqlReadL, executeBusinessSqlRead, executeBusinessSqlWrite, executeM4SingleValueSqlRead, executeM4SingleValueSqlReadL, executeM4SqlRead, executeM4SqlWrite, getArtificalColumnName, getBusinessDbms, getHighestLoopNr, getM4Db, getM4Dbms, getM4ObjectFromCache, getName, getNextM4SequenceValue, getNumberOfLoops, getOperator, getOpParamsIterator, getParameter, getParameter, getSingleParameter, getSingleParameter, getStep, handleAssertions, isDeselectedParameter, isLoopable, isManual, isStepable, print, putM4ObjectToCache, showCreateStatement, storedProceduresAvailable

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JoinByKey

public JoinByKey()

Method Detail

getTypeOfNewColumnSet

public java.lang.String getTypeOfNewColumnSet()

Description copied from class: SingleCSOperator

This method must return the entry String for the M4 table "Columnset_t", indicating whether the new Columnset is a view or a table.

Specified by:

getTypeOfNewColumnSet in class SingleCSOperator

Returns:

The type of the new Columnset, either "V" or "T".

See Also:

edu.udo.cs.miningmart.m4.core.operator.SingleCSOperator#getTypeOfNewColumnSet()

generateSQLDefinition

public java.lang.String generateSQLDefinition(java.lang.String selectPart)
                                       throws M4CompilerError

Description copied from class: SingleCSOperator

This method must return the SQL definition of the newly created ColumnSet.

Specified by:

generateSQLDefinition in class SingleCSOperator

Parameters:

selectPart - The SQL string between "SELECT" and "FROM" for the SQL definition to be returned.

Returns:

The SQL definition for the new ColumnSet.

Throws:

M4CompilerError

See Also:

edu.udo.cs.miningmart.m4.core.operator.SingleCSOperator#generateSQLDefinition(String)

generateColumns

protected java.lang.String generateColumns(Columnset csForOutputConcept)
                                    throws M4CompilerError

This method is overridden because the copying of columns from input to output concept works differently for this operator.

Overrides:

generateColumns in class ConceptOperator

Parameters:

csForOutputConcept - The ColumnSet for which Columns are to be produced.

Returns:

A String for the "SELECT"-part of the view definition for the given ColumnSet.

Throws:

M4CompilerError

See Also:

edu.udo.cs.miningmart.m4.core.operator.ConceptOperator(Columnset)

createMetadataForOneBA

protected java.lang.String createMetadataForOneBA(BaseAttribute inBA,
                                                  BaseAttribute outBA,
                                                  Columnset csForOutputConcept,
                                                  java.lang.String columnExpr)
                                           throws M4CompilerError

Overrides the superclass method because here a mapping is used.

Overrides:

createMetadataForOneBA in class ConceptOperator

Parameters:

inBA - A BaseAttribute from the input concept

outBA - The corresponding BaseAttribute from the output concept

csForOutputConcept - The current Columnset from the output concept

Returns:

An extended String for the Select part of the SQL statement

Throws:

M4CompilerError

See Also:

miningmart.compiler.operator.ConceptOperator#createMetadataForOneBA(BaseAttribute,BaseAttribute,Columnset,String)

setNewCSMultiStepBranch

protected void setNewCSMultiStepBranch(Columnset newCS,
                                       int index)
                                throws M4CompilerError

MultiStepBranch information of all Concepts need to be merged. In order to reduce the risk of different permutations of entries, which might be problematic with the current implementation of the Unsegment operator, the MultiStepBranch-Strings of all Columnsets are sorted before merging them. Multiple occurences of the same attribute are not supported; after the first occurence of an attribute each further occurence is removed.

Overrides:

setNewCSMultiStepBranch in class ConceptOperator

Parameters:

newCS - the Columnset that is created by this operator

index - An index for MulipleCSOperators.

Throws:

M4CompilerError

See Also:

ConceptOperator.setNewCSMultiStepBranch(Columnset, int), ConceptOperator.createSingleColumnSet(int)

getInputConcept

public Concept getInputConcept()

This method overrides the superclass method, so that it can still be used, although this operator has more than one input concept.

Overrides:

getInputConcept in class ConceptOperator

mustCopyFeature

protected boolean mustCopyFeature(java.lang.String nameOfFeature)

Description copied from class: ConceptOperator

This method is for operators that do not copy all Features of the input concept to the output concept.

Specified by:

mustCopyFeature in class ConceptOperator

Parameters:

nameOfFeature - Name of the feature in question.

Returns:

TRUE if this feature should be copied to the output concept, FALSE if not.

See Also:

edu.udo.cs.miningmart.m4.core.operator.ConceptOperator#mustCopyFeature(String)

getSortedConcepts

protected Concept[] getSortedConcepts()

Gets the parameters "TheConcepts".

Returns:

Returns a Concept[]

getSortedKeys

protected BaseAttribute[] getSortedKeys()

Gets the primary keys of TheConcepts.

Returns:

Returns a BaseAttribute[]

getInOutMap

protected Feature[][] getInOutMap()
                           throws M4CompilerError

Getter method for the mapping parameters.

Returns:

A two-dimensional array of Features. At position [0][i] is the ith "MapInput", at position [1][i] is the ith "MapOutput".

Throws:

M4CompilerError

load

public void load(Step st)
          throws ParameterDeselectedError,
                 M4CompilerError

Description copied from class: ExecutableOperator

Loads all parameters for this operator.

Overrides:

load in class ExecutableOperator

Parameters:

st - This executable operator's step

Throws:

ParameterDeselectedError

M4CompilerError

See Also:

Operator#load(Step)