[hibernate-issues] [Hibernate-JIRA] Resolved: (HHH-2436) Allow grouping by entity reference (per JPA spec)

Allow grouping by entity reference (per JPA spec) ------------------------------------------------- Key: HHH-2436 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-2436 Project: Hibernate3 Issue Type: Bug Components: query-hql Affects Versions: antlr-rework Reporter: Joseph Marques Assignee: Diego Pires Plentz Fix For: antlr-rework JPQL was: SELECT res.resourceType, count(res.resourceType) FROM ResourceGroup rg JOIN rg.resources res WHERE rg.id = :id GROUP BY res.resourceType It translated to: select resource2_.RESOURCE_TYPE_ID as col_0_0_, count(resource2_.RESOURCE_TYPE_ID) as col_1_0_, resourcety3_.ID as ID376_, resourcety3_.NAME as NAME376_, resourcety3_.DESCRIPTION as DESCRIPT3_376_, resourcety3_.CATEGORY as CATEGORY376_, resourcety3_.PLUGIN as PLUGIN376_, resourcety3_.CTIME as CTIME376_, resourcety3_.MTIME as MTIME376_, resourcety3_.PARENT_RESOURCE_TYPE_ID as PARENT8_376_, resourcety3_.PLUGIN_CONFIG_DEF_ID as PLUGIN9_376_, resourcety3_.RES_CONFIG_DEF_ID as RES10_376_ from public.ON_RESOURCE_GROUP resourcegr0_ inner join public.ON_RESOURCE_GROUP_RES_MAP resources1_ on resourcegr0_.ID=resources1_.RESOURCE_GROUP_ID inner join public.ON_RESOURCE resource2_ on resources1_.RESOURCE_ID=resource2_.ID inner join public.ON_RESOURCE_TYPE resourcety3_ on resource2_.RESOURCE_TYPE_ID=resourcety3_.ID where resourcegr0_.DTYPE in ( 'COMPATIBLE', 'MIXED' ) and resourcegr0_.ID=? group by resource2_.RESOURCE_TYPE_ID The message was: "ERROR main org.hibernate.util.JDBCExceptionReporter - ERROR: column "resourcety3_.id must appear in the GROUP BY caluse or be used in an aggregate function" My issue with this is that I only want to select a single object (along with the count of that object when grouped), but the generated SQL seems to be selecting two different objects - resource2_ and resourcety3_. The jdbc error message is perfectly correct; it's the translated SQL that seems a bit off. Maybe the JPQL syntax I want to use is not supported? Or perhaps I'm just doing something wrong?