MERGE_JOIN does not work with different mappings in joinKey?

Hi,

I encountered a problem when trying to join 3 files. File 1 is join to File 2 with key "REFERENCE", and File 1 is join to File 3 with key "NAME". The error from CloverETL is:

Graph definition file: palmer.grf
ERROR [main] - Can't create object of type EXT_MERGE_JOIN with reason: MERGE_JOIN:JOIN:Driver keys differ
Exception in thread "main" java.lang.RuntimeException: Can't create object of type EXT_MERGE_JOIN with reason: MERGE_JOIN:JOIN:Driver keys differ
at org.jetel.component.ComponentFactory.createComponent(ComponentFactory.java:132)
at org.jetel.graph.TransformationGraphXMLReaderWriter.instantiateNodes(TransformationGraphXMLReaderWriter.java:446)
at org.jetel.graph.TransformationGraphXMLReaderWriter.instantiatePhases(TransformationGraphXMLReaderWriter.java:409)
at org.jetel.graph.TransformationGraphXMLReaderWriter.read(TransformationGraphXMLReaderWriter.java:317)
at org.jetel.graph.runtime.GraphExecutor.loadGraph(GraphExecutor.java:213)
at org.jetel.graph.runtime.GraphExecutor.loadGraph(GraphExecutor.java:227)
at org.jetel.main.runGraph.main(runGraph.java:268)


here is my graph file:

<?xml version="1.0" encoding="UTF-8"?>
<Graph name="3FileJoins" revision="1.0">
<Global>
<Property fileURL="properties.prm"/>
<Metadata fileURL="${ROOT_PATH}/File1.fmt" id="InMetadata1"/>
<Metadata fileURL="${ROOT_PATH}/file2.fmt" id="InMetadata2"/>
<Metadata fileURL="${ROOT_PATH}/File3.fmt" id="InMetadata3"/>
<Metadata fileURL="${ROOT_PATH}/out.fmt" id="OutMetadata"/>
</Global>
<Phase number="0">
<Node id="INPUT1" type="DATA_READER" fileURL="${DATA}/File1.txt" skipFirstLine="true" quoteStrings="true"/>
<Node id="INPUT2" type="DATA_READER" fileURL="${DATA}/File2.txt" skipFirstLine="true" quoteStrings="true"/>
<Node id="INPUT3" type="DATA_READER" fileURL="${DATA}/File3.txt" skipFirstLine="true" quoteStrings="true"/>
<Node id="JOIN" type="EXT_MERGE_JOIN" joinKey="REFERENCE=REFERENCE#NAME=NAME" joinType="leftOuter" transformClass="ReformatJoinTest"/>
<Node id="OUTPUT" type="DELIMITED_DATA_WRITER" append="false" fileURL="${ROOT_PATH}/out.txt"/>

<Edge id="INEDGE1" fromNode="INPUT1:0" toNode="JOIN:0" metadata="InMetadata1"/>
<Edge id="INEDGE2" fromNode="INPUT2:0" toNode="JOIN:1" metadata="InMetadata2"/>
<Edge id="INEDGE3" fromNode="INPUT3:0" toNode="JOIN:2" metadata="InMetadata3"/>
<Edge fromNode="JOIN:0" id="JOINEDGE" metadata="OutMetadata" toNode="OUTPUT:0"/>
</Phase>
</Graph>


so does that mean that we cannot join files using different keys? or is my joinKey="REFERENCE=REFERENCE#NAME=NAME" not correct? isn't the first mapping "REFERENCE=REFERENCE" meant for File 1 to File 2, and second mapping "NAME=NAME" meant for File 1 to File 3?

Any suggestions/help is greatly appreciated :-)

al