Data mapping problem

Question

I posted this on OEPE too, but looks like this is a more appropriate forum. Copied from the other post
I'm creating a JCA service, and have done the following.
Use JDeveloper to create mapping to the DB table.
Use Oepe to create business service
Deploy service to OSB.
My Oracle table is very simple
timestamp - number(32) --primary key
itemid - number (20) --primary key
data - varchar2(3000)
my table.xsd file
xs:element name="TIMESTAMP" type="xs:decimal"
xs:element name="ITEMID" type="xs:decimal"
xs:element name="DATA" type="xs:string nillable="true"
my mapping file
<primary-key>
<field table="MYTABLE" name="ITEMID" xsi:type="column"/>
<field table="MYTABLE" name="TIMESTAMP" xsi:type="column"/>
</primary-key>
<attribute-mapping>
<attribute-name>timestamp</attribute-name>
<field table="MYTABLE" name="TIMESTAMP" xsi:type="column"/>
<attribute-classification>java.math.BigDecimal</attribute-classification>
</attribute-mapping>
<attribute-mapping>
<attribute-name>itemid</attribute-name>
<field table="MYTABLE" name="ITEMID" xsi:type="column"/>
<attribute-classification>java.math.BigDecimal</attribute-classification>
</attribute-mapping>
<attribute-mapping>
<attribute-name>data</attribute-name>
<field table="MYTABLE" name="DATA" xsi:type="column"/>
<attribute-classification>java.math.BigDecimal</attribute-classification>
</attribute-mapping>
the sql is
SELECT ORIG.DATA, ORIG.TIMESTAMP, ORIG.ITEMID from MYTABLE ORIG, (SELECT MAX(TIMESTAMP) AS MAXTIME, ITEMID FROM MYTABLE WHERE TIMESTAMP BETWEEN #low AND #high GROUP BY ITEMID) MAXRESULTS WHERE ORIG.TIMESTAMP = MAXRESULTS.MAXTIME AND ORIG.ITEMID=MAXRESULTS.ITEMID
As a result, I get the error The primary key read from the row during the execution of the query was detected to be null
The data record returned something like this
=>tabledata....
=>123455
MYTABLE.ITEMID =>12
So I know something is wrong with the mapping for data and timestamp. But everything was generated by jdeveloper. I have no idea what could be the problem. Does anyone know????? I've been looking into this for a while and I'm still lost.
Thanks in advance!

Answer 1

Odd, it seems that is cannot find the two fields in the result set. My guess is that database is not returning them in the result set meta-data, but not sure why. May have something to do with the sub-select in the from clause you are using.
Does it work if you remove the sub-select in the from clause?
If you take the same SQL and execute through session.executeSQL(), what field names are used in the resulting DatabaseRow? (or if you execute it in any other SQL tool?)
You could try aliasing the fields in the SQL to try to get their names in the meta-data.
James : http://www.eclipselink.org