Re: [hibernate-dev] Pull request for HHH-2394 (Support filter tag in subclass)

1) I think adding support for {alias} is a more general issue.  Its applicable to many other pieces of mapping metadata (@Formula, etc).  More I was responding to David's comment there.  I totally think it makes sense to support this in all of those cases.  I guess the vote point there is whether we want to introduce that support piecemeal or develop it across the board.  If we do do it piecemeal I think another piece of information we will need is a flag indicating whether to scan for alias injection points.  By "scanning" I mean the processing we do today where we tokenize the fragment string and then try to guess where an alias is needed.   Let's call this flag 'deduceAliasInjectionPoints' for now.  I tend to favor meaningful attribute names so my suggested names tend to get a little long; I am open to suggestions for a more succinct name.  Anyway, I think it needs to be TRUE by default to maintain backwards compatible behavior.  Here is an example: @Filter(name="iqMin", table="ZOOLOGY_HUMAN", condition="{alias}.HUMAN_IQ >= :min", deduceAliasInjectionPoints=false) Here there is no need to deduce the points at which to inject an alias; we have done that for Hibernate in the supplied condition fragment. I think another discussion revolves around cases in which the fragment involves references to columns from multiple tables.  Mostly this is important for scenarios involving secondary tables and inheritance.  Do we want to provide support for that?  Using the classic org.hibernate.test.hql.Animal hierarchy from the testsuite, maybe something like: @Filter(   name="iqMin",   condition="{a}.bodyWeight >= :minWeight and {m}.birthdate < :ageCutOffBirthDate",   deduceAliasInjectionPoints=false,   aliases={       @SqlFragmentAlias( alias="a", entity=Animal.class ),       @SqlFragmentAlias( alias="m", entity=Mammal.class )   } )