Mapping of Composite Keys

I have two tables with the below definition

CREATE TABLE VYA6CPP (
A6VN9K VARCHAR(9),
A6VN8K VARCHAR(8),
A6J2CD VARCHAR(20),
PRIMARY KEY(A6VN9K, A6VN8K)
)

CREATE TABLE MAMAM1 (
M1VIN1 VARCHAR(9),
M1VIN2 VARCHAR(8),
M1SHPR VARCHAR(4),
PRIMARY KEY(M1VIN1, M1VIN2),
FOREIGN KEY(M1VIN1, M1VIN2) REFERENCES VYA6CPP(A6VN9K, A6VN8K)
)

Below are the entity definition.








If the query <Select c from Mamam1 c> is executed, i get the below exception.

Hibernate: select mamam1x0_.M1VIN1 as M1_0_, mamam1x0_.M1VIN2 as M2_0_, mamam1x0_.M1SHPR as M3_0_ from MAMAM1 mamam1x0_ fetch first 10 rows only
java.lang.IllegalArgumentException: org.hibernate.TypeMismatchException: Provided id of the wrong type for class Vya6cpp. Expected: class Vya6cppPK, got class Mamam1PK
at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:247)
at Main.main(Main.java:26)
Caused by: org.hibernate.TypeMismatchException: Provided id of the wrong type for class Vya6cpp. Expected: class Vya6cppPK, got class Mamam1PK
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:135)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:1080)
at org.hibernate.impl.SessionImpl.internalLoad(SessionImpl.java:1028)
at org.hibernate.type.EntityType.resolveIdentifier(EntityType.java:623)
at org.hibernate.type.EntityType.resolve(EntityType.java:431)
at org.hibernate.engine.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:140)
at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:898)
at org.hibernate.loader.Loader.doQuery(Loader.java:773)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
at org.hibernate.loader.Loader.doList(Loader.java:2449)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2192)
at org.hibernate.loader.Loader.list(Loader.java:2187)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:452)
at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:363)
at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1258)
at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:241)
... 1 more

I'm facing a similar issue. I generated all of my classes using Hibernate tools and am using mapping files instead of annotations. In my scenario I have a composite ids for different classes that are made from the exact same table columns. Therefore the ids are the same when the load occurs.

Question: are the string values in both composite keys the same when you get this load error?

Not sure if this will help you, but I fixed my problem using the same composite id class for each one-to-one. Since they are all using the same table and columns, it makes sense. The generator missed it.

Good luck.

Sorry for the late reply. The entities were generated using Hibernate tools in eclipse. I tried running the mentioned query and i am still getting the error. I beleive in your case, the columns names of the composite keys were the same in both the tables. Regarding your question, I am not able to get it? To re-iterate my point, the columns names of the composite keys are different in both the tables.

That's a similar table structure to what I have. I don't have an explanation for it other than the 2 composite keys technically represent the same key (both tables share the same primary key)... so maybe Hibernate is tracking the keys by value and is finding a different class, but expecting the same class?

Anyway, I'm pretty sure if you change your code to use the class "Mamam1PK" as the identifier in your "Vya6cpp" class, you'll find things working. I updated my mapping and class files to have both classes use the same component id class and that resolved my problem.

It would be nice to get an official explanation for the issue though, in particular to understand if this is a bug or expected behavior. Did you log an incident on it yet?

If i have to use the same key class Mamam1PK in Vya6cpp, then it means that i have to change the columns names in the table VYA6CPP. But i need the mapping to work without changing the column names. Thanks for ur valuable comments and I will try to log an issue in JIRA.

I have raised an bug in JIRA https://hibernate.onjira.com/browse/HHH-6638. I have attached the test case and the table creation scripts, but i am not sure if it will get noticed by the official hibernate team.

I have been experience the exactly same problem... I make a query using HQL:


I used another mean of querying, namely:


But in both got the error mentioned (org.hibernate.TypeMismatchException: Provided id of the wrong type for class).

After some experiments, I ended up using "raw" SQL query:


and it worked as I wanted... i.e., I get the results I expect... however, you have to handle the results differently, cannot directly cast it to an hibernate object (obtained from the reverse engineering)... I had to work with the "Object", which basically contains the columns of the DB table. See http://wiki.webratio.com/index.php/Quer ... _Hibernate for a good explanation on querying with HQL and SQL...

...any ways, it would be nice to get it working with hibernate functionality (and objects)...

If native queries are used, it will return the List of object arrays which is kinda redundant and totally defeats the purpose and advantages of ORM, and a wastage of the Entity classes created. Thanks for your reply man and I have not received any kind of response to the JIRA bug raised. Is there any way for it to get noticed..?