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Posted to user@cayenne.apache.org by Dave Dombrosky <do...@gmail.com> on 2008/08/05 23:23:19 UTC
Using "relationship != null" qualifier with ObjEntity Inheritance
I am currently trying to use ObjEntity Inheritance in my project, but
I am running into some difficulties. I was hoping that I could use
"someRelationship != null" as the qualifier, but I get the following
error when trying to run the code:
org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
2008 19:55:10] Error evaluating expression 'db:some_relationship !=
null'
Am I doing something wrong here, or did I find a bug?
-Dave
Re: Using "relationship != null" qualifier with ObjEntity Inheritance
Posted by Andrus Adamchik <an...@objectstyle.org>.
Here is a more detailed answer. A case when a criteria for a
subclass / superclass is based on a presence of a given relationship
is better addressed with vertical inheritance - something we'll be
adding in 3.0. Single table inheritance mapping requires a criteria
based on one or more columns of the root table.
Andrus
On Aug 6, 2008, at 3:00 PM, Andrus Adamchik wrote:
>
> On Aug 6, 2008, at 2:54 PM, Dave Dombrosky wrote:
>
>> Do I have to add another column just to hold the type like the
>> documentation example shows? Not the best solution in this case, but
>> I guess it can be done if need be.
>
> That would certainly work.
>
> Andrus
>
>
Re: Using "relationship != null" qualifier with ObjEntity Inheritance
Posted by Andrus Adamchik <an...@objectstyle.org>.
On Aug 6, 2008, at 2:54 PM, Dave Dombrosky wrote:
> Do I have to add another column just to hold the type like the
> documentation example shows? Not the best solution in this case, but
> I guess it can be done if need be.
That would certainly work.
Andrus
Re: Using "relationship != null" qualifier with ObjEntity Inheritance
Posted by Dave Dombrosky <do...@gmail.com>.
Oh boy. What do you recommend in the meantime?
Do I have to add another column just to hold the type like the
documentation example shows? Not the best solution in this case, but
I guess it can be done if need be.
-Dave
On Wed, Aug 6, 2008 at 2:47 PM, Andrus Adamchik <an...@objectstyle.org> wrote:
> Ok, I see. This indeed is a limitation of the inheritance algorithm. We
> can't evaluate the inheritance qualifier expression in-memory in this case.
> We can probably improve on that in the future, but there is no easy fix.
>
> Andrus
>
>
> On Aug 6, 2008, at 2:29 PM, Dave Dombrosky wrote:
>
>> Yes it is just a 1:1 mapping on the relationship.
>>
>> Here is the stack trace:
>>
>> org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
>> 2008 19:55:10] Error evaluating expression 'db:some_relationship !=
>> null'
>> at
>> org.apache.cayenne.exp.parser.SimpleNode.evaluate(SimpleNode.java:331)
>> at org.apache.cayenne.exp.Expression.match(Expression.java:367)
>> at
>> org.apache.cayenne.map.EntityInheritanceTree.entityMatchingRow(EntityInheritanceTree.java:97)
>> at
>> org.apache.cayenne.map.EntityInheritanceTree.entityMatchingRow(EntityInheritanceTree.java:83)
>> at
>> org.apache.cayenne.access.ObjectResolver.objectFromDataRow(ObjectResolver.java:194)
>> at
>> org.apache.cayenne.access.ObjectResolver.objectsFromDataRows(ObjectResolver.java:121)
>> at
>> org.apache.cayenne.access.ObjectResolver.synchronizedObjectsFromDataRows(ObjectResolver.java:101)
>> at
>> org.apache.cayenne.access.DataDomainQueryAction$ObjectConversionStrategy.toObjects(DataDomainQueryAction.java:591)
>> at
>> org.apache.cayenne.access.DataDomainQueryAction$SingleObjectConversionStrategy.convert(DataDomainQueryAction.java:661)
>> at
>> org.apache.cayenne.access.DataDomainQueryAction.interceptObjectConversion(DataDomainQueryAction.java:466)
>> at
>> org.apache.cayenne.access.DataDomainQueryAction.execute(DataDomainQueryAction.java:128)
>> at
>> org.apache.cayenne.access.DataDomain.onQuery(DataDomain.java:740)
>> at
>> org.apache.cayenne.util.ObjectContextQueryAction.runQuery(ObjectContextQueryAction.java:317)
>> at
>> org.apache.cayenne.util.ObjectContextQueryAction.execute(ObjectContextQueryAction.java:96)
>> at
>> org.apache.cayenne.access.DataContext.onQuery(DataContext.java:1336)
>> at
>> org.apache.cayenne.access.DataContext.performQuery(DataContext.java:1325)
>> at
>> org.apache.cayenne.access.ToOneFault.doResolveFault(ToOneFault.java:82)
>> at
>> org.apache.cayenne.access.ToOneFault.resolveFault(ToOneFault.java:55)
>> at
>> org.apache.cayenne.CayenneDataObject.readProperty(CayenneDataObject.java:208)
>> at
>> org.apache.cayenne.CayenneDataObject.setToOneTarget(CayenneDataObject.java:295)
>>
>> -Dave
>>
>>
>> On Wed, Aug 6, 2008 at 11:59 AM, Andrus Adamchik <an...@objectstyle.org>
>> wrote:
>>>
>>> Could you post a bigger part of the stack trace (at least everything that
>>> has org.apache.cayenne in it)?
>>>
>>> From what I can see, this is related to in-memory evaluation of the
>>> qualifier. If that's a to-one relationship based on FK, intuitively this
>>> should work, but it probably hits a limitation on in-memory evaluation.
>>>
>>> Andrus
>>>
>>>
>>> On Aug 5, 2008, at 5:23 PM, Dave Dombrosky wrote:
>>>
>>>> I am currently trying to use ObjEntity Inheritance in my project, but
>>>> I am running into some difficulties. I was hoping that I could use
>>>> "someRelationship != null" as the qualifier, but I get the following
>>>> error when trying to run the code:
>>>>
>>>> org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
>>>> 2008 19:55:10] Error evaluating expression 'db:some_relationship !=
>>>> null'
>>>>
>>>> Am I doing something wrong here, or did I find a bug?
>>>>
>>>> -Dave
>>>>
>>>
>>>
>>
>
>
Re: Using "relationship != null" qualifier with ObjEntity Inheritance
Posted by Andrus Adamchik <an...@objectstyle.org>.
Ok, I see. This indeed is a limitation of the inheritance algorithm.
We can't evaluate the inheritance qualifier expression in-memory in
this case. We can probably improve on that in the future, but there is
no easy fix.
Andrus
On Aug 6, 2008, at 2:29 PM, Dave Dombrosky wrote:
> Yes it is just a 1:1 mapping on the relationship.
>
> Here is the stack trace:
>
> org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
> 2008 19:55:10] Error evaluating expression 'db:some_relationship !=
> null'
> at
> org.apache.cayenne.exp.parser.SimpleNode.evaluate(SimpleNode.java:331)
> at org.apache.cayenne.exp.Expression.match(Expression.java:367)
> at
> org
> .apache
> .cayenne
> .map
> .EntityInheritanceTree.entityMatchingRow(EntityInheritanceTree.java:
> 97)
> at
> org
> .apache
> .cayenne
> .map
> .EntityInheritanceTree.entityMatchingRow(EntityInheritanceTree.java:
> 83)
> at
> org
> .apache
> .cayenne.access.ObjectResolver.objectFromDataRow(ObjectResolver.java:
> 194)
> at
> org
> .apache
> .cayenne
> .access.ObjectResolver.objectsFromDataRows(ObjectResolver.java:121)
> at
> org
> .apache
> .cayenne
> .access
> .ObjectResolver.synchronizedObjectsFromDataRows(ObjectResolver.java:
> 101)
> at org.apache.cayenne.access.DataDomainQueryAction
> $ObjectConversionStrategy.toObjects(DataDomainQueryAction.java:591)
> at org.apache.cayenne.access.DataDomainQueryAction
> $SingleObjectConversionStrategy.convert(DataDomainQueryAction.java:
> 661)
> at
> org
> .apache
> .cayenne
> .access
> .DataDomainQueryAction
> .interceptObjectConversion(DataDomainQueryAction.java:466)
> at
> org
> .apache
> .cayenne
> .access.DataDomainQueryAction.execute(DataDomainQueryAction.java:128)
> at org.apache.cayenne.access.DataDomain.onQuery(DataDomain.java:740)
> at
> org
> .apache
> .cayenne
> .util
> .ObjectContextQueryAction.runQuery(ObjectContextQueryAction.java:317)
> at
> org
> .apache
> .cayenne
> .util.ObjectContextQueryAction.execute(ObjectContextQueryAction.java:
> 96)
> at org.apache.cayenne.access.DataContext.onQuery(DataContext.java:
> 1336)
> at
> org.apache.cayenne.access.DataContext.performQuery(DataContext.java:
> 1325)
> at
> org.apache.cayenne.access.ToOneFault.doResolveFault(ToOneFault.java:
> 82)
> at
> org.apache.cayenne.access.ToOneFault.resolveFault(ToOneFault.java:55)
> at
> org
> .apache
> .cayenne.CayenneDataObject.readProperty(CayenneDataObject.java:208)
> at
> org
> .apache
> .cayenne.CayenneDataObject.setToOneTarget(CayenneDataObject.java:295)
>
> -Dave
>
>
> On Wed, Aug 6, 2008 at 11:59 AM, Andrus Adamchik <andrus@objectstyle.org
> > wrote:
>> Could you post a bigger part of the stack trace (at least
>> everything that
>> has org.apache.cayenne in it)?
>>
>> From what I can see, this is related to in-memory evaluation of the
>> qualifier. If that's a to-one relationship based on FK, intuitively
>> this
>> should work, but it probably hits a limitation on in-memory
>> evaluation.
>>
>> Andrus
>>
>>
>> On Aug 5, 2008, at 5:23 PM, Dave Dombrosky wrote:
>>
>>> I am currently trying to use ObjEntity Inheritance in my project,
>>> but
>>> I am running into some difficulties. I was hoping that I could use
>>> "someRelationship != null" as the qualifier, but I get the following
>>> error when trying to run the code:
>>>
>>> org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
>>> 2008 19:55:10] Error evaluating expression 'db:some_relationship !=
>>> null'
>>>
>>> Am I doing something wrong here, or did I find a bug?
>>>
>>> -Dave
>>>
>>
>>
>
Re: Using "relationship != null" qualifier with ObjEntity Inheritance
Posted by Dave Dombrosky <do...@gmail.com>.
Yes it is just a 1:1 mapping on the relationship.
Here is the stack trace:
org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
2008 19:55:10] Error evaluating expression 'db:some_relationship !=
null'
at org.apache.cayenne.exp.parser.SimpleNode.evaluate(SimpleNode.java:331)
at org.apache.cayenne.exp.Expression.match(Expression.java:367)
at org.apache.cayenne.map.EntityInheritanceTree.entityMatchingRow(EntityInheritanceTree.java:97)
at org.apache.cayenne.map.EntityInheritanceTree.entityMatchingRow(EntityInheritanceTree.java:83)
at org.apache.cayenne.access.ObjectResolver.objectFromDataRow(ObjectResolver.java:194)
at org.apache.cayenne.access.ObjectResolver.objectsFromDataRows(ObjectResolver.java:121)
at org.apache.cayenne.access.ObjectResolver.synchronizedObjectsFromDataRows(ObjectResolver.java:101)
at org.apache.cayenne.access.DataDomainQueryAction$ObjectConversionStrategy.toObjects(DataDomainQueryAction.java:591)
at org.apache.cayenne.access.DataDomainQueryAction$SingleObjectConversionStrategy.convert(DataDomainQueryAction.java:661)
at org.apache.cayenne.access.DataDomainQueryAction.interceptObjectConversion(DataDomainQueryAction.java:466)
at org.apache.cayenne.access.DataDomainQueryAction.execute(DataDomainQueryAction.java:128)
at org.apache.cayenne.access.DataDomain.onQuery(DataDomain.java:740)
at org.apache.cayenne.util.ObjectContextQueryAction.runQuery(ObjectContextQueryAction.java:317)
at org.apache.cayenne.util.ObjectContextQueryAction.execute(ObjectContextQueryAction.java:96)
at org.apache.cayenne.access.DataContext.onQuery(DataContext.java:1336)
at org.apache.cayenne.access.DataContext.performQuery(DataContext.java:1325)
at org.apache.cayenne.access.ToOneFault.doResolveFault(ToOneFault.java:82)
at org.apache.cayenne.access.ToOneFault.resolveFault(ToOneFault.java:55)
at org.apache.cayenne.CayenneDataObject.readProperty(CayenneDataObject.java:208)
at org.apache.cayenne.CayenneDataObject.setToOneTarget(CayenneDataObject.java:295)
-Dave
On Wed, Aug 6, 2008 at 11:59 AM, Andrus Adamchik <an...@objectstyle.org> wrote:
> Could you post a bigger part of the stack trace (at least everything that
> has org.apache.cayenne in it)?
>
> From what I can see, this is related to in-memory evaluation of the
> qualifier. If that's a to-one relationship based on FK, intuitively this
> should work, but it probably hits a limitation on in-memory evaluation.
>
> Andrus
>
>
> On Aug 5, 2008, at 5:23 PM, Dave Dombrosky wrote:
>
>> I am currently trying to use ObjEntity Inheritance in my project, but
>> I am running into some difficulties. I was hoping that I could use
>> "someRelationship != null" as the qualifier, but I get the following
>> error when trying to run the code:
>>
>> org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
>> 2008 19:55:10] Error evaluating expression 'db:some_relationship !=
>> null'
>>
>> Am I doing something wrong here, or did I find a bug?
>>
>> -Dave
>>
>
>
Re: Using "relationship != null" qualifier with ObjEntity Inheritance
Posted by Andrus Adamchik <an...@objectstyle.org>.
Could you post a bigger part of the stack trace (at least everything
that has org.apache.cayenne in it)?
From what I can see, this is related to in-memory evaluation of the
qualifier. If that's a to-one relationship based on FK, intuitively
this should work, but it probably hits a limitation on in-memory
evaluation.
Andrus
On Aug 5, 2008, at 5:23 PM, Dave Dombrosky wrote:
> I am currently trying to use ObjEntity Inheritance in my project, but
> I am running into some difficulties. I was hoping that I could use
> "someRelationship != null" as the qualifier, but I get the following
> error when trying to run the code:
>
> org.apache.cayenne.exp.ExpressionException: [v.3.0-SNAPSHOT Aug 01
> 2008 19:55:10] Error evaluating expression 'db:some_relationship !=
> null'
>
> Am I doing something wrong here, or did I find a bug?
>
> -Dave
>