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Issue Using Hibernate Criteria object with composite key

Answer 1

A:

The mapping you've posted and the description you provided conflict with each other:

Mapping join column on inverse association as non-insertable/updatable is not going to work. How is that column going to be updated (and your parent-child association maintained)?
Your child mapping defines Child's PK as childId (using @Id annotation). That's NOT how a composite key is mapped; Hibernate will consider childId to be a simple primary key.
Your criteria doesn't match your mapping (ParentTable vs Parent, etc...) which is probably a conversion artifact, but other then that looks OK.

I'd use aliases, though:

Criteria criteria = session.createCriteria(Parent.class)
 .add(Restrictions.eq("policyNo", "1234"))
 .createAlias("child", "children")
 .add(Restrictions.ne("children.transType", "VIEW"));

Update (based on criteria / generated SQL):

Take a look at the SQL generated by Hibernate based on your criteria (shortened for readability):

SELECT this_.*, ts1_.*, copolicypo4_.*
  FROM CoPolicyPointer this_
 INNER JOIN CoTransactionSummary ts1_ ON this_.systemAssignId=ts1_.systemAssignId
  LEFT JOIN CoPolicyPointer copolicypo4_ ON ts1_.systemAssignId=copolicypo4_.systemAssignId

You'll notice that your "parent" table (CoPolicyPointer) is joined twice even though your criteria only joins the "children" table. That happens because you're specifying entity names in @Entity annotations but creating your criteria using original class name, making Hibernate think you're joining three separate entities:

Criteria is based on CoPolicyPointerRedo.class
It joins to CoTransactionSummaryRedo.class whose entity name is CoTransactionSummary
Which joins back to CoPolicyPointerRedo.class as `CoPolicyPointer using @ManyToOne

You need to be consistent with naming. Either remove name from @Entity declarations (you can use @Table instead to specify table name) or create your criteria using session.createCriteria(String entityName) method which takes entity name rather than class name as parameter.

ChssPly76 2009-10-19 21:01:10

I have removed the insertable=false and updatable=false from the annotation as suggested. In regards to your second point, you are correct that the @ID annotation was incorrect and my code actually has @EmbeddedId. I had to create a seperate example because I'm not supposed to share the companies code on the internet and didn't realize I used the wrong annotation. Sorry for the confusion.I changed the criteria code to what you have above and I still get back 3 of the Parent objects instead of just 1 with the child records attached.Any other ideas?

jwmajors81 2009-10-19 21:14:15

I sympathize with "not sharing the code" but I don't think posting just the relevant fragments (and changing entity names like you did) would be objectionable - otherwise it's hard to suggest the solution without seeing the exact problem. @EmbeddedId you've mentioned should be (is?) applied to another (component) class. How is the cihld's part of that composite id assigned? Did you enable SQL output in Hibernate? If so, what query is generated? Does it look reasonable based on your data or do you see something obviously wrong?

ChssPly76 2009-10-19 21:21:22

I have tried what you suggested, but I still get an extra left outer join tacked onto the end of the SQL. I was able to get a distinct result back by adding the following to the criteria statement: criteria .setResultTransformer(DistinctRootEntityResultTransformer.INSTANCE);However, that is less than idea because all of the records are returned from the database and hibernate has to determine which record to use, so I would still like to find another option.

jwmajors81 2009-10-22 23:18:08

Left outer join is there because you're querying children - how else would you do it? However, "parent" instances you get back should all be the same in that case, so applying transformer to results is the proper way to do this.

ChssPly76 2009-10-22 23:23:28

Within the query hibernate first does an inner join between CoPolicyPointer and CoTransactionSummary and then joins again between the same two tables doing a left outer join. Wouldn't the second query be redundant? Also, why would it return multiple parent entities, a couple that don't have any children while the third does have the expected child records. I know that there is only one record in the parent table that matches the criteria and then 3 CoTransactionSummary records. I would expect hibernate to return a single parent entity with 3 child entities.

jwmajors81 2009-10-23 01:03:37

So this happens _after_ you've removed the entity names from your annotations? There should be no 2nd join and the 1st join should be outer.

ChssPly76 2009-10-23 02:09:19

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Issue Using Hibernate Criteria object with composite key

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