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

[Steve Ebersole]

And by the way, I think you are right in that if there are any explicit 
SqlFragmentAlias bits supplied, that we infer 
'deduceAliasInjectionPoints' as being false.

On 06/25/2012 08:29 AM, Rob Worsnop wrote:
> Got it. Earlier you were looking for suggestions for a less verbose name
> for this. How about "autoAliasInjection"?
>
> On Mon, Jun 25, 2012 at 8:20 AM, Steve Ebersole <steve at hibernate.org
> <mailto:steve at hibernate.org>> wrote:
>
>     'deduceAliasInjectionPoints' is important when you don't have
>     injections.  Otherwise Hibernate ends up scanning the condition
>     fragment for no reason.
>
>
>     On Fri 22 Jun 2012 11:09:31 AM CDT, Rob Worsnop wrote:
>
>         On Mon, Jun 4, 2012 at 12:14 PM, Steve Ebersole
>         <steve at hibernate.org <mailto:steve at hibernate.org>> wrote:
>
>             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 )
>                }
>             )
>
>
>         How about just applying the secondary table usage to everything?
>
>         So, to rewrite your first example:
>
>         @Filter(name="iqMin", condition="{h}.HUMAN_IQ >=> :min",
>              aliases={@SqlFragmentAlias( alias="h",
>         table="ZOOLOGY_HUMAN" )})
>
>         Note that I didn't include "deduceAliasInjectionPoints". Wouldn't we
>         just infer that from the presence of the aliases element?
>
>
>     --
>     steve at hibernate.org <mailto:steve at hibernate.org>
>     http://hibernate.org
>
>

-- 
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