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Posted to ojb-dev@db.apache.org by Mike Ahlers <mi...@hippo.nl> on 2004/04/07 18:33:48 UTC
Problem with OJB - foreign keys
Hi,
I have a certain problem with OJB. Originally I posted this on cocoon
dev, but since this is ojb related I am posting here as well.
Let me describe what I got so far. After digging deeper into this and
producing some relevant debug statements I find the following written on
my console:
console output:
--- start snippet ---
NVTPDataAccessObject2: getArticle: called with id: 56
[org.apache.ojb.broker.accesslayer.JdbcAccessImpl] DEBUG: executeQuery :
Query from class nl.hippo.nvpt.Articles where [id = 56]
[org.apache.ojb.broker.accesslayer.sql.SqlGeneratorDefaultImpl] DEBUG:
SQL:SELECT
A0.TELEFOON,A0.TREFWOORDEN,A0.TYPE,A0.PARTNER,A0.PASSWORD,A0.KLANT,A0.LOGIN,A0
.WERKZAAMBIJ,A0.TITEL,A0.OMSCHRIJVING,A0.MATRICE_ID,A0.EMAIL,A0.CONTACTPERSOON,A0.BESTAND,A0.CORP_ID,A0.BRON,A0.ID
FROM ARTICLES A0 WHERE A0.ID = ?
[org.apache.ojb.broker.accesslayer.JdbcAccessImpl] DEBUG: executeQuery:
com.mysql.jdbc.PreparedStatement@13c33b7: SELECT
A0.TELEFOON,A0.TREFWOORDEN,A0.TYPE,A0.PARTNER,A0.PASSWORD,A0.KLANT,A0.LOGIN,A0.WERKZAAMBIJ,A0.TITEL,A0.OMSCHRIJVING,A0.
MATRICE_ID,A0.EMAIL,A0.CONTACTPERSOON,A0.BESTAND,A0.CORP_ID,A0.BRON,A0.ID
FROM ARTICLES A0 WHERE A0.ID = 56
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG:
RsIterator[org.apache.ojb.broker.accesslayer.RsQueryObject[query: Query
from class nl.hippo.nvpt.Articles where [id = 56], class descriptor:
nl.hippo.nvpt.Articles]] initialized
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> true
[org.apache.ojb.broker.accesslayer.sql.SqlGeneratorDefaultImpl] DEBUG:
SQL:SELECT NAAM,OMSCHRIJVING,ID FROM ARTICLE_TYPES WHERE ID = ?
[org.apache.ojb.broker.accesslayer.JdbcAccessImpl] DEBUG: executeQuery :
Query from class nl.hippo.nvpt.Articles where [type = 3]
^^^^^^
[org.apache.ojb.broker.accesslayer.sql.SqlGeneratorDefaultImpl] DEBUG:
SQL:SELECT
A0.TELEFOON,A0.TREFWOORDEN,A0.TYPE,A0.PARTNER,A0.PASSWORD,A0.KLANT,A0.LOGIN,A0
.WERKZAAMBIJ,A0.TITEL,A0.OMSCHRIJVING,A0.MATRICE_ID,A0.EMAIL,A0.CONTACTPERSOON,A0.BESTAND,A0.CORP_ID,A0.BRON,A0.ID
FROM ARTICLES A0 WHERE A0.TYPE = ?
[org.apache.ojb.broker.accesslayer.JdbcAccessImpl] DEBUG: executeQuery:
com.mysql.jdbc.PreparedStatement@1f8f8c8: SELECT
A0.TELEFOON,A0.TREFWOORDEN,A0.TYPE,A0.PARTNER,A0.PASSWORD,A0.KLANT,A0.LOGIN,A0.WERKZAAMBIJ,A0.TITEL,A0.OMSCHRIJVING,A0.
MATRICE_ID,A0.EMAIL,A0.CONTACTPERSOON,A0.BESTAND,A0.CORP_ID,A0.BRON,A0.ID
FROM ARTICLES A0 WHERE A0.TYPE = 3
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG:
RsIterator[org.apache.ojb.
broker.accesslayer.RsQueryObject[query: Query from class
nl.hippo.nvpt.Articles where [type = 3], class descriptor:
nl.hippo.nvpt.Articles]] initialized
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> true
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> true
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> true
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> true
...
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> true
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> true
[org.apache.ojb.broker.accesslayer.RsIterator] DEBUG: hasNext() -> false
java.lang.ArithmeticException: / by zero
at
org.apache.ojb.broker.accesslayer.BasePrefetcher.<init>(BasePrefetcher.java:115)
at
org.apache.ojb.broker.accesslayer.RelationshipPrefetcherImpl.<init>(RelationshipPrefetcherImpl.java:78)
at
org.apache.ojb.broker.accesslayer.CollectionPrefetcher.<init>(CollectionPrefetcher.java:97)
at
org.apache.ojb.broker.accesslayer.RelationshipPrefetcherFactory.createRelationshipPrefetcher(RelationshipPrefetcherFactory.java:85)
at
org.apache.ojb.broker.core.QueryReferenceBroker.performRetrievalTasks(QueryReferenceBroker.java:315)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(QueryReferenceBroker.java:185)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(QueryReferenceBroker.java:242)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(QueryReferenceBroker.java:262)
at
org.apache.ojb.broker.core.QueryReferenceBroker.retrieveCollection(QueryReferenceBroker.java:513)
at
org.apache.ojb.broker.core.QueryReferenceBroker.retrieveCollections(QueryReferenceBroker.java:695)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getDBObject(PersistenceBrokerImpl.java:1153)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.doGetObjectByIdentity(PersistenceBrokerImpl.java:1217)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getReferencedObject(QueryReferenceBroker.java:478)
at
org.apache.ojb.broker.core.QueryReferenceBroker.retrieveReference(QueryReferenceBroker.java:358)
at
org.apache.ojb.broker.core.QueryReferenceBroker.retrieveReferences(QueryReferenceBroker.java:400)
at
org.apache.ojb.broker.accesslayer.RsIterator.getObjectFromResultSet(RsIterator.java:501)
at
org.apache.ojb.broker.accesslayer.RsIterator.next(RsIterator.java:293)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getObjectByQuery(PersistenceBrokerImpl.java:1298)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getObjectByQuery(DelegatingPersistenceBroker.java:291)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getObjectByQuery(DelegatingPersistenceBroker.java:291)
at nl.hippo.nvpt.NVTPDataAccessObject2.getArticle(Unknown Source)
--- end snippet ---
Note the sudden 'translation' of 'Article_types' into 'Articles'. I am
expecting a query like: Query from class nl.hippo.nvpt.Article_types
where [type = 3] and not Query from class nl.hippo.nvpt.Articles where
[type = 3]. Could this a bug in the SqlGeneratorDefaultImpl regarding
nested queries? Anyways, this is what I am trying to map:
repository.xml:
--- start snippet ---
<class-descriptor class="nl.hippo.nvpt.Articles" table="ARTICLES">
<field-descriptor name="id" primarykey="true" default-fetch="true"
column="ID" jdbc-type="INTEGER"/>
<field-descriptor name="type" default-fetch="true" column="TYPE"
jdbc-type="INTEGER"/>
....
<reference-descriptor name="article_types"
class-ref="nl.hippo.nvpt.Article_types" auto-update="false"
auto-delete="false">
<foreignkey field-ref="type"/>
</reference-descriptor>
</class-descriptor>
--- end snippet ---
The following classes are generated (like the repository.xml) by Druid
and has setters and getters.
Articles.java:
--- start snippet ---
public class Articles {
public int id;
public int type;
public Article_types article_types;
...
}
--- end snippet ---
Article_types:
--- start snippet ---
public class Article_types
{
public int id;
public String naam;
public String omschrijving;
}
--- end snippet ---
My data access object looks like this:
--- start snippet ---
public Articles getArticle(int id) {
...
System.out.println("NVTPDataAccessObject2: getArticle: called with id: "
+ id);
broker = PersistenceBrokerFactory.defaultPersistenceBroker();
// Create criteria
criteria = new Criteria();
criteria.addEqualTo("id", new Integer(id)); // Refine criteria
// Create query
query = new QueryByCriteria(Articles.class, criteria);
result = (Articles) broker.getObjectByQuery(query);
...
return result;
--- end snippet ---
Any suggestions?
Mike Ahlers
Brian McCallister wrote:
> Any chance you can post the relevent repository_user.xml snippets and
> an outline at least of what they map to? More than happy to help you
> work out what's going on =)
>
> I have never seen divide by zero errors from OJB =(
>
> Also, do you get the same problem if you try the query via the
> PersistenceBroker api instead of the JDO api?
>
> -Brian
>
> On Apr 7, 2004, at 5:44 AM, Mike Ahlers wrote:
>
>> Hi,
>>
>> I am a new kid on the block and work with the OJB/JDO block. Using a
>> database with no relations works perfectly, however when I increase
>> complexity and use foreign keys I fail to get it working. The
>> following error is what I get:
>>
>> [org.apache.ojb.broker.accesslayer.RsIterator] ERROR: Error while
>> iterate Result Set for query
>> org.apache.ojb.broker.accesslayer.RsQueryObject[query: Query from
>> class nl.hippo.nvpt.Articles where [id = 55], class descriptor:
>> nl.hippo.nvpt.Ar
>> ticles]
>> / by zero java.lang.ArithmeticException: / by zero
>>
>> Can anybody explain why iterating over a result-set gives a div by zero?
>>
>> Thanks in advance,
>> Mike Ahlers
>>
>>
>
>
>
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