From what I can tell, nobody ever looked at this scenario (EJBQL with
generic entities) yet, so I am not surprised it is broken. Let me log
a Jira to investigate the issue. Sorry, this also means you'll have to
use SQLTemplate.
Andrus
On Jun 10, 2009, at 12:14 AM, Dave Lamy wrote:
Hey guys-- I'm trying to get group functions operational in my
Cayenne-backed system. As far as I can tell, the only support for
group
functions (min, max, count, etc) outside of rolling my own SQL is
EJBQL.. is
that true or am I missing something?
Assuming this is the case: I'm having issues with my EJBQL working
when I
reference a generic Cayenne class. IE, my "Artist" data class
doesn't have
a strong class implementation.. it just uses a standard base class.
This
feature has been great and is absolutely essential to our software.
However, in my test case I have a simple Artist class with no
concrete impl:
<obj-entity name="Artist" lock-type="optimistic" dbEntityName="ARTIST"
superClassName="com.routeto1.data.DynamicDataObject">
<obj-attribute name="address" type="java.lang.String"
db-attribute-path="ADDRESS"/>
<obj-attribute name="name" type="java.lang.String"
db-attribute-path="NAME"/>
<obj-attribute name="type" type="java.lang.String"
db-attribute-path="TYPE"/>
</obj-entity>
when I try to execute a simple EJBQL group test query:
select count(a), a.name from Artist a group by a.name
I get the following exception:
org.apache.cayenne.CayenneRuntimeException: [v.3.0M5 Nov 29 2008
21:12:47]
Can't perform lookup. There is more than one ObjEntity mapped to
com.routeto1.data.impl.DynamicDataObject
at
org
.apache
.cayenne.map.EntityResolver._lookupObjEntity(EntityResolver.java:847)
at
org
.apache
.cayenne.map.EntityResolver.lookupObjEntity(EntityResolver.java:701)
at
org
.apache
.cayenne.query.BaseQueryMetadata.resolve(BaseQueryMetadata.java:99)
at
org
.apache
.cayenne.query.SQLTemplateMetadata.resolve(SQLTemplateMetadata.java:
47)
at
org.apache.cayenne.query.SQLTemplate.getMetaData(SQLTemplate.java:157)
at
org
.apache
.cayenne.access.jdbc.SQLTemplateAction.<init>(SQLTemplateAction.java:
77)
at
org
.apache
.cayenne.dba.JdbcActionBuilder.sqlAction(JdbcActionBuilder.java:90)
at
org
.apache
.cayenne.access.jdbc.EJBQLAction.performAction(EJBQLAction.java:100)
at
org
.apache
.cayenne
.access.DataNodeQueryAction.runQuery(DataNodeQueryAction.java:57)
at
org.apache.cayenne.access.DataNode.performQueries(DataNode.java:236)
at
org
.apache
.cayenne
.access.DataDomainQueryAction.runQuery(DataDomainQueryAction.java:423)
at
org.apache.cayenne.access.DataDomainQueryAction.access
$000(DataDomainQueryAction.java:67)
....
which seems to read like the EJBQL impl doesn't support the generic
base
class concept. Am I right on this? I don't care about EJBQL, just
want to
get group functions working without having to resort to rolling a
bunch of
dynamic SQL :-). Perhaps an upgrade to M6 is in order? Thanks in
advance
for any help you can provide!
--Dave Lamy
