Re: collection loading and filtering
Hi Jakob,
I think you have not seen my last post :)
JAVA code =
package test.ojb;
import java.util.Vector;
public class A {
private int oid;
private String name = null;
private Vector elements = null;
public A() {
super();
}
public A(String name) {
super();
this.name = name;
}
public void add(B b){
if(elements == null) elements = new Vector();
elements.addElement(b);
}
public boolean isEqual(A a){
return this.oid == a.getOid();
}
public int getOid() {
return oid;
}
}
package test.ojb;
public class B {
private int oid;
private String value = null;
private String filter = null;
public B(){
super();
}
public B(String filter, String value) {
super();
this.filter = filter;
this.value = value;
}
public boolean isEqual(B b){
return this.oid == b.getOid();
}
public int getOid() {
return oid;
}
public String getFilter() {
return filter;
}
public String getValue() {
return value;
}
}
package test.ojb;
import java.util.Collection;
import org.apache.log4j.Category;
import org.apache.log4j.Logger;
import org.apache.ojb.broker.PersistenceBroker;
import org.apache.ojb.broker.PersistenceBrokerFactory;
import org.apache.ojb.broker.query.Criteria;
import org.apache.ojb.broker.query.Query;
import org.apache.ojb.broker.query.QueryByCriteria;
import org.apache.ojb.broker.query.QueryFactory;
/**
* Projection test with OJB 1.0.0
*/
public class ProjectionTest {
private static Category logger = null;
private PersistenceBroker broker = null;
public ProjectionTest(){
if(logger == null) logger = Logger.getInstance(ProjectionTest.class) ;
this.broker = PersistenceBrokerFactory.defaultPersistenceBroker();
}
public static void main(String[] args) {
ProjectionTest projectionTest = new ProjectionTest();
// uncomment the following line to initialize the database
//projectionTest.initDB();
// load the collection with a SQL statement
B[] sqlResult = projectionTest.getFilteredArray1(xxx, yyy);
// load the collection with OJB projection
B[] ojbResult = projectionTest.getFilteredArray2(xxx, yyy);
if(sqlResult != null ojbResult != null){
if(sqlResult.length == ojbResult.length){
logger.info(result size SQL == result size OJB );
// log obj results
for (int i=0;iojbResult.length;i++)
logger.info(B + ojbResult[i].getFilter() + , +
ojbResult[i].getValue() + );
}
else
logger.info(result size SQL != result size OJB - Test KO.);
}
}
public void initDB(){
// objects with a relationship 1:N
A a1 = new A(xxx);
A a2 = new A(fff);
// populate the elements relationship
for(int i=0; i3;i++){
// a1 contains two categories of filter
a1.add(new B(yyy, aby + i));
a1.add(new B(zzz, abz + i));
// a2 contains two categories of filter
a2.add(new B(yyy, bby + i));
a2.add(new B(zzz, bbz + i));
}
broker.beginTransaction();
// store all into the DB (auto-update=true)
broker.store(a1);
broker.store(a2);
broker.commitTransaction();
// make sure the relationship is loaded from the DB
broker.serviceObjectCache().clear();
}
// example realized with a SQL (SQL92) statement
public B[] getFilteredArray1(String name, String filter){
B[] ret = null;
StringBuffer sqlStatement = new StringBuffer();
sqlStatement.append(select b.* from T_A a, T_B b where b.a_oid=A.oid and
a.name=');
sqlStatement.append(name);
sqlStatement.append(' and b.filter=');
sqlStatement.append(filter);
sqlStatement.append(');
Query query = QueryFactory.newQuery(B.class, sqlStatement.toString());
Collection col = broker.getCollectionByQuery(query);
broker.serviceObjectCache().clear();
if(col != null){
ret = new B[col.size()];
col.toArray(ret);
}
return ret;
}
// example realize with a SQL (SQL92) statement
public B[] getFilteredArray2(String name, String filter){
B[] ret = null;
Criteria criteria = new Criteria();
// criteria relative to A
criteria.addEqualTo(name, name);
criteria.addEqualTo(elements.filter, filter);
QueryByCriteria query = QueryFactory.newQuery(A.class, criteria);
query.setObjectProjectionAttribute(elements);
Collection col = broker.getCollectionByQuery(query);
broker.serviceObjectCache().clear();
if(col != null){
ret = new B[col.size()];
col.toArray(ret);
}
return ret;
}
}
== SQL for Oracle 8i ===
SPOOL projtest.log
drop table T_A;
create table T_A (
OID INTEGER NOT NULL,
name VARCHAR2 ( 16 ) NULL,
constraint PK_A PRIMARY KEY (OID)
);
commit;
drop table T_B;
create table T_B (
OID INTEGER NOT NULL,
filter VARCHAR2 ( 16 ) NULL,
value VARCHAR2 ( 16 ) NULL,
a_OID INTEGER NULL,
constraint PK_B PRIMARY KEY (OID)
);
commit;
SPOOL OFF
Exit 0 ;
.
/
=== repository.xml ==
Re: collection loading and filtering
table T_B ( OID INTEGER NOT NULL, filter VARCHAR2 ( 16 ) NULL, value VARCHAR2 ( 16 ) NULL, a_OID INTEGER NULL, constraint PK_B PRIMARY KEY (OID) ); commit; SPOOL OFF Exit 0 ; . / === repository.xml == ?xml version='1.0' encoding='ISO-8859-1' ? descriptor-repository version=1.0 isolation-level=read-uncommitted proxy-prefetching-limit=50 !-- Datasource for Proto1, this connection is used as the default -- !-- Driver P6Spy : com.p6spy.engine.spy.P6SpyDriver -- !-- Driver Oracle : oracle.jdbc.driver.OracleDriver -- jdbc-connection-descriptor jcd-alias=sim default-connection=true platform=Oracle jdbc-level=2.0 driver=com.p6spy.engine.spy.P6SpyDriver protocol=jdbc subprotocol=oracle:thin dbalias=@xx username=xxx password=xxx eager-release=false batch-mode=false useAutoCommit=1 ignoreAutoCommitExceptions=false sequence-manager className=org.apache.ojb.broker.util.sequence.SequenceManagerNextValImpl attribute attribute-name=autoNaming attribute-value=true/ /sequence-manager /jdbc-connection-descriptor !-- Mapping -- class-descriptor class=test.ojb.A table=T_A isolation-level=read-uncommitted accept-locks=true refresh=true field-descriptor name=oid column=oid jdbc-type=INTEGER primarykey=true autoincrement=true nullable=false/ field-descriptor name=name column=name jdbc-type=VARCHAR/ !-- elements relationship -- collection-descriptor name=elements element-class-ref=test.ojb.B auto-update=true auto-retrieve=true auto-delete=true proxy=true inverse-foreignkey field-ref=aOid/ /collection-descriptor /class-descriptor class-descriptor class=test.ojb.B table=T_B isolation-level=read-uncommitted accept-locks=true refresh=true field-descriptor name=oid column=oid jdbc-type=INTEGER primarykey=true autoincrement=true/ field-descriptor name=filter column=filter jdbc-type=VARCHAR/ field-descriptor name=value column=value jdbc-type=VARCHAR/ field-descriptor name=aOid column=a_OID jdbc-type=INTEGER access=anonymous/ /class-descriptor /descriptor-repository == END source == Gildas - Original Message - From: Jakob Braeuchi [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 6:55 PM Subject: Re: collection loading and filtering hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
Hi Jakob, I post that today. Gildas - Original Message - From: Jakob Braeuchi [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 6:55 PM Subject: Re: collection loading and filtering hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob LE-QUERE Gildas - REN schrieb: Excellent! that's right. Thanks for your help Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 4:27 PM Subject: Re: collection loading and filtering query.setObjectProjectionAttribute(elements) will solve your problem Hi Alexander, I tried your suggestion. With the addPrefetchedRelationship()method all elements of the relationship are loaded. The filter criteria, here, is a condition to retrieve the A object. In fact it's the right behaviour for this request. The problem is to realize a kind of left outer join in OOP to get the Collection of B which belong to A. In fact I use the A data to find some B elements. Now I think to load a filtered relationship is not very good idea. As a last resort I can use the sqlStatement but I loose the transparency of the persistence. Thanks Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 2:25 PM Subject: Re: collection loading and filtering did you try query.addPrefetchedRelationship(elements) ? Hi all, I have un object A referencing à collection with B elements. A has an attribute 'name' and a relation 'elements', B has an attribute 'filter'. I want to load elements where name='xxx' and filter='yyy'. I use the PersitenceBroker API, here is my request: criteria = new Criteria(); criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); query = QueryFactory.newQuery(A.class, criteria); A a = (A)broker.getObjectByQuery(query); With the relationship auto-retrieve=true all elements are loaded! If auto-retrieve=false the relationship is not loaded. Is there a solution ? Thanks Gildas - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
Hi Jakob You will find in attachment my test case on Oracle 8i best regards Gildas - Original Message - From: Jakob Braeuchi [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 6:55 PM Subject: Re: collection loading and filtering hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
== ?xml version='1.0' encoding='ISO-8859-1' ? descriptor-repository version=1.0 isolation-level=read-uncommitted proxy-prefetching-limit=50 !-- Datasource for Proto1, this connection is used as the default -- !-- Driver P6Spy : com.p6spy.engine.spy.P6SpyDriver -- !-- Driver Oracle : oracle.jdbc.driver.OracleDriver -- jdbc-connection-descriptor jcd-alias=sim default-connection=true platform=Oracle jdbc-level=2.0 driver=com.p6spy.engine.spy.P6SpyDriver protocol=jdbc subprotocol=oracle:thin dbalias=@xx username=xxx password=xxx eager-release=false batch-mode=false useAutoCommit=1 ignoreAutoCommitExceptions=false sequence-manager className=org.apache.ojb.broker.util.sequence.SequenceManagerNextValImpl attribute attribute-name=autoNaming attribute-value=true/ /sequence-manager /jdbc-connection-descriptor !-- Mapping -- class-descriptor class=test.ojb.A table=T_A isolation-level=read-uncommitted accept-locks=true refresh=true field-descriptor name=oid column=oid jdbc-type=INTEGER primarykey=true autoincrement=true nullable=false/ field-descriptor name=name column=name jdbc-type=VARCHAR/ !-- elements relationship -- collection-descriptor name=elements element-class-ref=test.ojb.B auto-update=true auto-retrieve=true auto-delete=true proxy=true inverse-foreignkey field-ref=aOid/ /collection-descriptor /class-descriptor class-descriptor class=test.ojb.B table=T_B isolation-level=read-uncommitted accept-locks=true refresh=true field-descriptor name=oid column=oid jdbc-type=INTEGER primarykey=true autoincrement=true/ field-descriptor name=filter column=filter jdbc-type=VARCHAR/ field-descriptor name=value column=value jdbc-type=VARCHAR/ field-descriptor name=aOid column=a_OID jdbc-type=INTEGER access=anonymous/ /class-descriptor /descriptor-repository == END source == Gildas - Original Message - From: Jakob Braeuchi [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 6:55 PM Subject: Re: collection loading and filtering hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
hi gildas, the attachment did not make it to the list. please post the sql as normal text. jakob LE-QUERE Gildas - REN schrieb: Hi Jakob You will find in attachment my test case on Oracle 8i best regards Gildas - Original Message - From: Jakob Braeuchi [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 6:55 PM Subject: Re: collection loading and filtering hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: collection loading and filtering
That'd be cool - I've never even heard of it, and a search of the mailing list archives only turns up references in code for patches. Anyone got a handy description of what projectionAttribute does (and how it's different to, say, prefetchedRelationship) ? Cheers, Charles. -Original Message- From: Jakob Braeuchi [mailto:[EMAIL PROTECTED] Sent: 27 October 2004 17:55 To: OJB Users List Subject: Re: collection loading and filtering hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob LE-QUERE Gildas - REN schrieb: Excellent! that's right. Thanks for your help Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 4:27 PM Subject: Re: collection loading and filtering query.setObjectProjectionAttribute(elements) will solve your problem Hi Alexander, I tried your suggestion. With the addPrefetchedRelationship()method all elements of the relationship are loaded. The filter criteria, here, is a condition to retrieve the A object. In fact it's the right behaviour for this request. The problem is to realize a kind of left outer join in OOP to get the Collection of B which belong to A. In fact I use the A data to find some B elements. Now I think to load a filtered relationship is not very good idea. As a last resort I can use the sqlStatement but I loose the transparency of the persistence. Thanks Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 2:25 PM Subject: Re: collection loading and filtering did you try query.addPrefetchedRelationship(elements) ? Hi all, I have un object A referencing à collection with B elements. A has an attribute 'name' and a relation 'elements', B has an attribute 'filter'. I want to load elements where name='xxx' and filter='yyy'. I use the PersitenceBroker API, here is my request: criteria = new Criteria(); criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); query = QueryFactory.newQuery(A.class, criteria); A a = (A)broker.getObjectByQuery(query); With the relationship auto-retrieve=true all elements are loaded! If auto-retrieve=false the relationship is not loaded. Is there a solution ? Thanks Gildas --- -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] ___ HPD Software Ltd. - Helping Business Finance Business Email terms and conditions: www.hpdsoftware.com/disclaimer - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
hi charles, imo projectionAttributes and prefetcheRelationships are two completely different things. afaik (after trying to write a testcase) projectionAttribute change the search_class of a query. jakob Charles Anthony schrieb: That'd be cool - I've never even heard of it, and a search of the mailing list archives only turns up references in code for patches. Anyone got a handy description of what projectionAttribute does (and how it's different to, say, prefetchedRelationship) ? Cheers, Charles. -Original Message- From: Jakob Braeuchi [mailto:[EMAIL PROTECTED] Sent: 27 October 2004 17:55 To: OJB Users List Subject: Re: collection loading and filtering hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob LE-QUERE Gildas - REN schrieb: Excellent! that's right. Thanks for your help Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 4:27 PM Subject: Re: collection loading and filtering query.setObjectProjectionAttribute(elements) will solve your problem Hi Alexander, I tried your suggestion. With the addPrefetchedRelationship()method all elements of the relationship are loaded. The filter criteria, here, is a condition to retrieve the A object. In fact it's the right behaviour for this request. The problem is to realize a kind of left outer join in OOP to get the Collection of B which belong to A. In fact I use the A data to find some B elements. Now I think to load a filtered relationship is not very good idea. As a last resort I can use the sqlStatement but I loose the transparency of the persistence. Thanks Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 2:25 PM Subject: Re: collection loading and filtering did you try query.addPrefetchedRelationship(elements) ? Hi all, I have un object A referencing à collection with B elements. A has an attribute 'name' and a relation 'elements', B has an attribute 'filter'. I want to load elements where name='xxx' and filter='yyy'. I use the PersitenceBroker API, here is my request: criteria = new Criteria(); criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); query = QueryFactory.newQuery(A.class, criteria); A a = (A)broker.getObjectByQuery(query); With the relationship auto-retrieve=true all elements are loaded! If auto-retrieve=false the relationship is not loaded. Is there a solution ? Thanks Gildas --- -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] ___ HPD Software Ltd. - Helping Business Finance Business Email terms and conditions: www.hpdsoftware.com/disclaimer - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
Hi David, With the following code criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); I get A, but alos all elements of th relationship and not only the B elements where filter ='yyy'. Finaly it's right because the filter= 'yyy' is a criteria to retrieve A. I have a big volumetry on B, so I took your advice, to load the collection programmaticaly. If later I need all elements I have the proxy to navigate on the relationship. A solution would be like the following SQL statement: select B.* from A, B where A.name='xxx' and B.A_id =A.id and B.filter='yyy' (with A_id foreign key of A in B table) Thanks a lot for your help. Gildas - Original Message - From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 10:33 AM Subject: RE: collection loading and filtering Hi Gildas, According to me, the two approachs are not compatible. - If you are trying to get A and B in only one query: Then the following code criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); is the way. And you will get A WITH the filtered collection of B. And I don't see why you don't want to load the relationship, because a join query is executed because you want the relationships. - If you try to avoid unnecessary relationships loading: Then the proxy is the solution. And in this case the filtering cannot be done automatically. You have to do it programmatically by adding a method like A.getB(int yyy) where you implement your filter. If you are taking of performance, first do it as simple as possible, then look if you face performance issues. Personally, I generally choose the second approach and I use the first one only in case of performance issues (but only monitoring can say what to do). Then I have two methods: A getById(); // criteria.addEqualTo(name, 'xxx') and use proxy A getByIdWithB(); // criteria.addEqualTo(name, 'xxx') criteria.addEqualTo(elements.filter, 'yyy') Be also aware that caching the objects increases performance. If B contains rather stable data, then cache them. A.getB() will then use the cache instead of generating a SQL. Hope it helps... David WIESZTAL. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
Hi Alexander, I tried your suggestion. With the addPrefetchedRelationship()method all elements of the relationship are loaded. The filter criteria, here, is a condition to retrieve the A object. In fact it's the right behaviour for this request. The problem is to realize a kind of left outer join in OOP to get the Collection of B which belong to A. In fact I use the A data to find some B elements. Now I think to load a filtered relationship is not very good idea. As a last resort I can use the sqlStatement but I loose the transparency of the persistence. Thanks Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 2:25 PM Subject: Re: collection loading and filtering did you try query.addPrefetchedRelationship(elements) ? Hi all, I have un object A referencing à collection with B elements. A has an attribute 'name' and a relation 'elements', B has an attribute 'filter'. I want to load elements where name='xxx' and filter='yyy'. I use the PersitenceBroker API, here is my request: criteria = new Criteria(); criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); query = QueryFactory.newQuery(A.class, criteria); A a = (A)broker.getObjectByQuery(query); With the relationship auto-retrieve=true all elements are loaded! If auto-retrieve=false the relationship is not loaded. Is there a solution ? Thanks Gildas - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
query.setObjectProjectionAttribute(elements) will solve your problem Hi Alexander, I tried your suggestion. With the addPrefetchedRelationship()method all elements of the relationship are loaded. The filter criteria, here, is a condition to retrieve the A object. In fact it's the right behaviour for this request. The problem is to realize a kind of left outer join in OOP to get the Collection of B which belong to A. In fact I use the A data to find some B elements. Now I think to load a filtered relationship is not very good idea. As a last resort I can use the sqlStatement but I loose the transparency of the persistence. Thanks Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 2:25 PM Subject: Re: collection loading and filtering did you try query.addPrefetchedRelationship(elements) ? Hi all, I have un object A referencing à collection with B elements. A has an attribute 'name' and a relation 'elements', B has an attribute 'filter'. I want to load elements where name='xxx' and filter='yyy'. I use the PersitenceBroker API, here is my request: criteria = new Criteria(); criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); query = QueryFactory.newQuery(A.class, criteria); A a = (A)broker.getObjectByQuery(query); With the relationship auto-retrieve=true all elements are loaded! If auto-retrieve=false the relationship is not loaded. Is there a solution ? Thanks Gildas - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
Excellent! that's right. Thanks for your help Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 4:27 PM Subject: Re: collection loading and filtering query.setObjectProjectionAttribute(elements) will solve your problem Hi Alexander, I tried your suggestion. With the addPrefetchedRelationship()method all elements of the relationship are loaded. The filter criteria, here, is a condition to retrieve the A object. In fact it's the right behaviour for this request. The problem is to realize a kind of left outer join in OOP to get the Collection of B which belong to A. In fact I use the A data to find some B elements. Now I think to load a filtered relationship is not very good idea. As a last resort I can use the sqlStatement but I loose the transparency of the persistence. Thanks Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 2:25 PM Subject: Re: collection loading and filtering did you try query.addPrefetchedRelationship(elements) ? Hi all, I have un object A referencing à collection with B elements. A has an attribute 'name' and a relation 'elements', B has an attribute 'filter'. I want to load elements where name='xxx' and filter='yyy'. I use the PersitenceBroker API, here is my request: criteria = new Criteria(); criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); query = QueryFactory.newQuery(A.class, criteria); A a = (A)broker.getObjectByQuery(query); With the relationship auto-retrieve=true all elements are loaded! If auto-retrieve=false the relationship is not loaded. Is there a solution ? Thanks Gildas - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: collection loading and filtering
hi gildas, could you please post the sql without and with projectionAttribute. i'd like to write a testcase and eventually document this feature. jakob LE-QUERE Gildas - REN schrieb: Excellent! that's right. Thanks for your help Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 4:27 PM Subject: Re: collection loading and filtering query.setObjectProjectionAttribute(elements) will solve your problem Hi Alexander, I tried your suggestion. With the addPrefetchedRelationship()method all elements of the relationship are loaded. The filter criteria, here, is a condition to retrieve the A object. In fact it's the right behaviour for this request. The problem is to realize a kind of left outer join in OOP to get the Collection of B which belong to A. In fact I use the A data to find some B elements. Now I think to load a filtered relationship is not very good idea. As a last resort I can use the sqlStatement but I loose the transparency of the persistence. Thanks Gildas - Original Message - From: Maksimenko Alexander [EMAIL PROTECTED] To: OJB Users List [EMAIL PROTECTED] Sent: Wednesday, October 27, 2004 2:25 PM Subject: Re: collection loading and filtering did you try query.addPrefetchedRelationship(elements) ? Hi all, I have un object A referencing à collection with B elements. A has an attribute 'name' and a relation 'elements', B has an attribute 'filter'. I want to load elements where name='xxx' and filter='yyy'. I use the PersitenceBroker API, here is my request: criteria = new Criteria(); criteria.addEqualTo(name, 'xxx'); criteria.addEqualTo(elements.filter, 'yyy'); query = QueryFactory.newQuery(A.class, criteria); A a = (A)broker.getObjectByQuery(query); With the relationship auto-retrieve=true all elements are loaded! If auto-retrieve=false the relationship is not loaded. Is there a solution ? Thanks Gildas - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
