OJB 1.0.4 ODMG implementation
Hi, I just played around with ODMG and tried to execute the following OQL: select x from myClass where attribute is not in ( select distinct y.id from anotherClass ) During OQLQuery q.create(oql) OJB writes a message to stderr with unexpected token (select) and throws an Exception: java.lang.NoSuchMethodError: org.apache.ojb.odmg.oql.OQLParser.recover(Lantlr/RecognitionException;Lantlr/collections/impl/BitSet;)V at org.apache.ojb.odmg.oql.OQLParser.argList(Unknown Source) at org.apache.ojb.odmg.oql.OQLParser.inExpr(Unknown Source) at org.apache.ojb.odmg.oql.OQLParser.quantifierExpr(Unknown Source) at org.apache.ojb.odmg.oql.OQLParser.andExpr(Unknown Source) at org.apache.ojb.odmg.oql.OQLParser.orExpr(Unknown Source) at org.apache.ojb.odmg.oql.OQLParser.whereClause(Unknown Source) at org.apache.ojb.odmg.oql.OQLParser.selectQuery(Unknown Source) at org.apache.ojb.odmg.oql.OQLParser.buildQuery(Unknown Source) at org.apache.ojb.odmg.oql.OQLQueryImpl.create(Unknown Source) at org.apache.ojb.odmg.oql.OQLQueryImpl.create(Unknown Source) Am I right in assuming, that OJB does not support such subqueries? Retrieving the Collection from the subquery and then explicitely generating an not in expression does the job, however the subquery result could be quite large. Best regards Bernd Längerich
AW: OJB Development Activity
Armin wrote: Sorry for the delay. I took a few sabbatical weeks from OJB to spend more time with my (newborn) daughter and currently I have some problems with my eyes, which makes it difficult to work on OJB. Armin, congrats to your newborn family member, all the best to all of your family and take care of your eyes. Bernd - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
AW: what's with OJB Project?
Armin Waibel writes: Well, it depends on the community. Currently it seems that only a few people are able to (interested in) spend time for OJB. I will continue my work on OJB. I would like to say thank you for your efforts. I would also like to offer my best to support OJB in future but I have to check with the company policy first. Maybe I can contribute to the project, as I already made some efforts to enhance OJB for our companies purposes. Best regards Bernd - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
AW: Question regarding metadata handling in ojb 1.0.4
Armin Waibel wrote: Since ClassB is an extent of ClassA the merge of the repositories isn't enough. The merge method is intended to merge/add new classes without dependencies to already registered classes. You could try to use the ClassDescriptor.addExtent(...) method to register a new extent: MetadataManager mm = MetadataManager.getInstance(); DescriptorRepository dr = mm.readDescriptorRepository(my/additional/plugin_repository.xml); mm.mergeDescriptorRepository(dr); //then lookup the repository DescriptorRepository repo = mm.getRepository(); // lookup the CLD of ClassA ClassDescriptor cldA = repo.getDescriptorFor(ClassA.class); // add the new extent cldA.addExtent(ClassB); I never tried this ;-) Heureka, it works! Thanks Armin. I am now a big step further. As all informations regarding the registration of the extent classes could be in the additional repository file to merge, it should be possible to add these lines of code to ojb, but I am unaware if this will break other things. Next 3 weeks are holiday, so maybe I will have a look inside ojbs sourcecode. Best regards Bernd - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Question regarding metadata handling in ojb 1.0.4
Hi,
I am trying to find some information regarding metadata merging in the
following scenario:
We have a base application with some classes, db tables and a
repository_user.xml that describes the mapping.
Lets say we have a base class BasePersistentClassA and some classes that are
based which are included as extent classes in the xml file.
This application is running.
No we develop an optional plugin with a class PluginPersistentClassB that is
based on BasePersistentClassA of the application.
I can now write an additional repository.xml and merge it with:
MetadataManager mm = MetadataManager.getInstance();
DescriptorRepository dr =
mm.readDescriptorRepository(my/additional/plugin_repository.xml);
mm.mergeDescriptorRepository(dr);
However I am failing to get the correct contents regarding the extent-class
definitions of the base class.
I tried to include the following to plugin_repository.xml:
class-descriptor
class=BasePersistentClassA
extent-class class-ref=PluginPersistentClassB/
/class-descriptor
class-descriptor
class=PluginPersistentClassB
table=MyTable
...
/class-descriptor
Something is strange, as the following code fragment does not delete anything
at the first broker.deleteByQuery() and fails at the second one:
Criteria crit = new Criteria();
crit.addNotEqualTo(ojbConcreteClass,BaseApplicationClassX.class.getName());
Query q = QueryFactory.newQuery(Transaction.class,crit);
broker.deleteByQuery(q);
// SELECT DISTINCT ACC_TAID FROM ACC_TA
ReportQueryByCriteria subquery = new
ReportQueryByCriteria(BasePersistentClassA .class,null);
subquery.setAttributes(new String[] { id });
subquery.setDistinct(true);
Criteria crit = new Criteria();
crit.addNotIn(externalID,subquery);
Query q = QueryFactory.newQuery(Another.class,crit);
broker.deleteByQuery(q);
It seems that the extent definitions from dr are not merged and even corrupt
the existing definitions of the application, as trying to access all classes
from the database results in an NullPointerException:
2007.07.26 17:40:33,375 [0/ServiceRequestDispatcher-P=3/T=7-running:1/1/1] INFO
cleardb: start
java.lang.NullPointerException
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement$TableAlias.hashCode(Unknown
Source)
at java.util.HashMap.hash(Unknown Source)
at java.util.HashMap.put(Unknown Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.splitCriteria(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.init(Unknown Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlSelectStatement.init(Unknown Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.getSubQuerySQL(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.appendSubQuery(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.appendParameter(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.appendInCriteria(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.appendCriteria(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.appendSQLClause(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.asSQLStatement(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.appendClause(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.appendWhereClause(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlDeleteByQuery.buildStatement(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.sql.SqlQueryStatement.getStatement(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeDelete(Unknown Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.deleteByQuery(Unknown Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.deleteByQuery(Unknown Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.deleteByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.deleteByQuery(Unknown
Source)
[...]
If I include the table= part, I get the NullPointerException at:
so it seems that the existing class definition is not merged with the
additional data but overwritten.
Ommiting the extent-class-definitions from the additional xml file, I can
access all classes of the base application, but not of the plugin. As we have
several plugins, we dont want any dependencies from the base application to the
plugins.
Any hints are appreciated.
Best regards
Bernd
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
AW: SequenceManagerHighLowImpl
Bernd Ingrid Laengerich wrote:
OK, I played around a little bit and overwrote the afterStore
method (empty implementation, however it never gets called!?
What am I missing? I placed a breakpoint in my code, but it
never reaches it.
OK, searching around a little bit, I found in JdbcAccessImpl:
protected void assignAutoincrementIdentityColumns(ClassDescriptor cld,
Object target) throws SequenceManagerException
{
// if database Identity Columns are used, query the id from database
// other SequenceManager implementations will ignore this call
if(cld.useIdentityColumnField())
broker.serviceSequenceManager().afterStore(this, cld, target);
}
This seems to be the only place where this method is called directly, except it
is called via reflection.
I will just write a refresh method, as the locations are countable where such
inserts of alien data rows are used.
Bernd
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
AW: SequenceManagerHighLowImpl
Hi Armin, thanks again for your response. Armin wrote: Längerich wrote: Is it sufficient/possible to overwrite the afterStore() method of the sequence manager? Yep it's possible. Assume you want to lookup the HLSequence-object for the current used (fixed) field and invalidate the current used PK value or declare that the next sequence value has to greater than this to avoid duplicate PK values. Think this should work (except if an concurrent thread request the next value before the current thread can invalidate it). OK, I played around a little bit and overwrote the afterStore method (empty implementation, however it never gets called!? What am I missing? I placed a breakpoint in my code, but it never reaches it. My code is somhehow simple, writeing a line to stderr to see if anything happens at all. If the code is of any interest: http://rafb.net/p/hknTM276.html Bernd - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
SequenceManagerHighLowImpl
Hi, I have some problems with OJB (PB-API) and the sequence manager. I derived a new sequence manager from the shipped HighLowImpl, that checks for every grab size with SequenceManagerHelper.getMaxForExtent() for the max id of the field. This works fine with data added externally, but I have a situation where the original HighLowImpl and my version fails: Given the scenario, where the application has created an instance of the sequence manager for the PK field and inserts some data with fixed field contents from another source, with a pk field contents of any value in the current range of prefetched ids (grabsize), I get a dup key constraints error when the sequence manager reaches these rows. The background is, that we store each row to a primary data base and a backup data base. Whenever the computer with the primary data base crashes, it can be restored from an automatic backup, but this will be up to several hours old, so we recover the missing data from the backup data base and store them to the primary db (using OJB PB-Api). Is there any way of forcing the sequence manager to be recreated? At the moment I have a workaround with fetching grabSize ids with Identity oid = broker.serviceIdentity().buildIdentity(Object newPersistentObject); Is it sufficient/possible to overwrite the afterStore() method of the sequence manager? Best regards Bernd - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Problem/misunderstanding with ObjectCache, multiple databases and ObjectModification, 1.0.4
Hi,
I have some problems understanding (and using) the concept of the cache when
using multiple databases and determining the object modification level at the
store method.
Assume we have two databases A and B with one being the default and one being
the backup database. Both connections are configured using the cache:
object-cache class=org.apache.ojb.broker.cache.ObjectCacheDefaultImpl
attribute attribute-name=timeout attribute-value=-1/
/object-cache
Given the following code sequence with empty databases, I have some problems:
AnObject someObject = new AnObject();
[...]
PersistenceBroker defaultBroker =
PersistenceBrokerFactory.defaultPersistenceBroker();
defaultbroker.store(someObject); // resulting in an INSERT to the default DB
[...]
defaultBroker.store(someObject); // resulting in an UPDATE to the default DB
PersistenceBroker backupBroker =
PersistenceBrokerFactory.createPersistenceBroker(new PBKey(backup));
backupBroker.store(someObject); // resulting in an UPDATE to the backup DB,
which fails as there is no such row in the DB
As far as I understand the code from PersistanceBrokerImpl, it should query the
cache and/or the DB:
/*
if PK values are set, lookup cache or db to see whether object
needs insert or update
*/
if (!insert)
{
insert = objectCache.lookup(oid) == null
!serviceBrokerHelper().doesExist(cld, oid, obj);
}
store(obj, oid, cld, insert);
The insert should be false, as the PK fields are not null, and the objectCache
for the backupBroker should give null.
I traced with P6Spy, but I can't detect a SELECT to determine the existence of
the row, so I assume the objectCache.lookup(oid) returns true.
Any hints?
Bernd
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
AW: Problem/misunderstanding with ObjectCache, multiple databases and ObjectModification, 1.0.4
Hi Armin, thank you for your fast response. Armin Waibel writes: You are right, OJB find the object in the cache (because you operate with the same objects on different DB's using a shared cache) and indicate to update the object instead of insert. Do you really need a shared cache on your backup broker? I would recommend to use a per broker cache (for backup-broker) http://db.apache.org/ojb/docu/guides/objectcache.html#ObjectCachePerBrokerImpl Then OJB will not find the object in the cache of backup-broker and perform a DB select. Okay, thanks for the clarification. I was not aware, that the ObjectCacheDefaultImpl is shared amongst all connections as I declared the cache at connection level, but reading the words global and static Map in the documentation really helps :-). As we create a broker on demand and discard it after single use, the per broker cache is not helpful at all, so I will use ObjectCacheEmptyImpl. Bernd - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Merging data from two data bases
Hi,
given is a master data base and a backup data base. All entries are stored to
the master data base and to the backup.
If anything fails (computer crashes) at startup I want to merge the data from
the backup with the data of the master database.
The code I tried is like this:
masterbroker = PersistenceBrokerFactory.defaultPersistenceBroker();
ReportQueryByCriteria masterquery =
QueryFactory.newReportQuery(Transaction.class,new Criteria());
masterquery.setAttributes(new String[] {id});
masterquery.setDistinct(true);
Collection taids = masterbroker.getCollectionByQuery(masterquery);
log.info(Master DB has +taids.size()+ transactions);
Criteria crit = new Criteria();
crit.addNotIn(id,taids);
backupbroker = PersistenceBrokerFactory.createPersistenceBroker(new
PBKey(jcdalias));
Query query = QueryFactory.newQuery(Transaction.class,crit);
Collection tas = backupbroker.getCollectionByQuery(query);
if (tas.size()0) {
log.warn(Backup DB has +tas.size()+ transactions not stored in the
master DB);
}
for (Iterator iter = tas.iterator(); iter.hasNext();) ...
The problem is when I reach the line
Collection taids = masterbroker.getCollectionByQuery(masterquery);
I get a strange exception:
org.apache.ojb.broker.PersistenceBrokerException: Unexpected error while try to
read 'ojbConcretClass' field from result set using column name CLASS_NAME main
class was de.actosoft.accept.process.Transaction
at
org.apache.ojb.broker.accesslayer.RowReaderDefaultImpl.extractOjbConcreteClass(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.RowReaderDefaultImpl.readObjectArrayFrom(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.RsIterator.getObjectFromResultSet(Unknown
Source)
at org.apache.ojb.broker.accesslayer.RsIterator.next(Unknown Source)
at org.apache.ojb.broker.accesslayer.ChainingIterator.next(Unknown
Source)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(Unknown
Source)
[...]
The strange thing is the 'ojbConcretClass' where the repository_user.xml says:
class-descriptor
class=de.actosoft.accept.process.NullTransaction
table=ACC_TA
field-descriptor
name=ojbConcreteClass
column=CLASS_NAME
jdbc-type=VARCHAR
length=255
/field-descriptor
field-descriptor
name=id
column=ACC_TAID
jdbc-type=INTEGER
primarykey=true
autoincrement=true
[...]
The SQL generated and executed looks fine (except that it contains redundant
where clause parts):
1165921756841|-1||resultset|SELECT DISTINCT A0.ACC_TAID FROM ACC_TA A0 WHERE (
A0.CLASS_NAME IN (...)) AND (A0.CLASS_NAME IN (...)|ACC_TAID = 1
If I remove the line
masterquery.setAttributes(new String[] {id});
everything works fine but I get all object instances instead of just a
collection of ids.
Any hints? Is there any way to do what I want? I used db-ojb-1.0.4.jar and
MS-SQL 2000.
Mit freundlichen Grüßen
i.A. Bernd Längerich
Softwareentwicklung
act'o-soft GmbH Payment Systems
World Wide Business Center
Habichtstrasse 41
22305 Hamburg
Phone: 00 49 40 61135432
Fax: 00 49 40 61135429
Mobile: -
eMail: [EMAIL PROTECTED]
www.actosoft-payment-systems.de
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
Re: Merging data from two data bases
Ingrid Längerich writes:
The code I tried is like this:
OK, I found out that
Iterator it = masterbroker.getReportQueryIteratorByQuery(masterquery);
Collection taids = new Vector();
while (it.hasNext()) {
Object obj = ((Object[])it.next())[0];
taids.add(obj);
}
is working. Is there a better way to achieve the same result?
Bernd
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
1.03 PB-API broker.deleteBy() and QueryByCriteria problem
Hi, a criteria with path expressions like in the OJB queries reference guide example (http://db.apache.org/ojb/docu/guides/query.html#Query+by+Criteria) does not work for me with broker.deleteByQuery(q). Using Microsoft SQL Server, the resulting statement of the example Criteria crit = new Criteria(); crit.addEqualTo(productGroup.groupName, Liquors); Query q = QueryFactory.newQuery(Article.class, crit); Collection results = broker.getCollectionByQuery(q); results in the correct JOIN in the SELECT statement, but using: broker.deleteByQuery(q); results in a statement, where the path expression ist not expanded but the statement executed is something like DELETE FROM Artikel WHERE KategorieName='Liquors' but I expected something like DELETE FROM Artikel WHERE Kategorie_Nr IN (SELECT Kategorie_Nr FROM Kategorien WHERE KategorieName='Liquors') Any hints? Mit freundlichen Grüßen i.A. Bernd Längerich -- www.actosoft.de - Key Solutions for Retail - ac news Marktgeflüster ac news Marktgeflüster Smarter Fashion - neue Geschäftsmodelle und integrierte Lösungen für die Fashion Value Chain +++ Das Seminar am 12.09.2006 im Zeughaus Neuss +++ Weitere Infos unter: www.microsoft.com/germany/events/fashion __ act'o-soft GmbH Informationssysteme * Enger Str. 12 * D-33824 Werther (Westf.) Tel.: +49-5203-9744-40 * Fax: +49-5203-9744-41 * eMail: [EMAIL PROTECTED] Sitz der Gesellschaft ist Werther (Westf.) * Amtsgericht Gütersloh * HRB 5242 Geschäftsführer: Christian Malachowski * Dipl.-Ing. Michael Schramm ___ ___ This e-mail including any attachments may contain information that is legally privileged and confidential. It constitutes non-public information intended to be conveyed only to the designated recipient(s). If you are not an intended recipient please delete this e-mail and any attachments and do not read, copy, or retransmit it and please notify act'o-soft GmbH by return mail, e-mail or at +49/5203/974440. The unauthorized use, dissemination, distribution or reproduction of this e-mail, including attachments, is prohibited and may be unlawful. ___ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
