[hibernate-dev] Some insight about HHH-12101 / remove HQL-style positional parameters

[Laurent Almeras]

Thanks for your feedback.

As I currently use QueryDSL generated queries, it's not easy to switch 
the way my queries are generated.

I post an issue with a github branch with some simple test-cases here: 
https://hibernate.atlassian.net/browse/HHH-12290


Laurent Almeras


Le 07/02/2018 à 19:43, Steve Ebersole a écrit :
> And I did say that this is indeed a problem assuming you are right, 
> and I have no reason to believe you are not.  In fact I can see how 
> that would happen.  Yes all based on Hibernate internals.
>
> So I am not trying to blow you off as "this is not a bug". I think it 
> is a bug.  I'm just saying I do not yet know what to do about it.
>
> On Wed, Feb 7, 2018 at 12:41 PM Steve Ebersole <steve at hibernate.org 
> <mailto:steve at hibernate.org>> wrote:
>
>     Yes, I understood the situation.
>
>     I'm saying that in your query you should just be able to switch to
>     use named parameters (prefixed with `:`, rather than `?`) as a
>     workaround
>
>     On Wed, Feb 7, 2018 at 11:21 AM Laurent Almeras
>     <laurent.almeras at laposte.net <mailto:laurent.almeras at laposte.net>>
>     wrote:
>
>         Hi,
>
>         Thanks for this insight ; but as I stated (and this is a
>         correction of the assumptions of my first email) in my second
>         email, it seems that the wrong query (with mixed positional
>         and named parameters) is built in hibernate inside layers (and
>         not in QueryDSL).
>
>         I get rid of my QueryDSL query and replace it with raw JPQL
>         query :
>
>
>         ============================
>                 Query query = getEntityManager().createQuery("select
>         queuedTaskHolder\n" +
>                         "from QueuedTaskHolder queuedTaskHolder\n" +
>                         "where queuedTaskHolder.status in (?1) and
>         queuedTaskHolder.queueId = ?2\n" +
>                         "order by queuedTaskHolder.id
>         asc").setParameter(1, ImmutableList.of(TaskStatus.CANCELLED,
>         TaskStatus.COMPLETED)).setParameter(2, "queue");
>                 return query.getResultList();
>         ============================
>
>         And it fails with the very same message :
>
>
>         ============================
>
>
>         Cannot define positional and named parameterSpecs : select
>         queuedTaskHolder
>         from
>         org.iglooproject.jpa.more.business.task.model.QueuedTaskHolder
>         queuedTaskHolder
>
>         where queuedTaskHolder.status in (:x1_0, :x1_1) and
>         queuedTaskHolder.queueId = ?2
>         order by queuedTaskHolder.id asc
>             at
>         org.hibernate.hql.internal.ast.HqlSqlWalker.generatePositionalParameter(HqlSqlWalker.java:1094)
>             at
>         org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.parameter(HqlSqlBaseWalker.java:3463)
>         ============================
>
>         It used to work with Hibernate 5.2.x ; and by reading JPQL
>         spec (not sure if this is the right version -
>         https://docs.oracle.com/html/E13946_01/ejb3_langref.html#ejb3_langref_in
>         ) it seems that " IN (?param) " is a valid syntax.
>
>         I agree that mixed query may not be supported, but even if
>         positional parameter queries bring nothing more than named
>         parameters ones, there are also required for JPA compliance ?
>
>         Can you say me if I made some wrong assumptions ? If not, is
>         it usefull I provide some minimal test-case ?
>
>
>
>         *Side-note:* same query written with named parameters is OK
>         (as expected):
>
>
>         ============================
>                 Query query = getEntityManager().createQuery("select
>         queuedTaskHolder\n" +
>                 "from QueuedTaskHolder queuedTaskHolder\n" +
>                 "where queuedTaskHolder.status in (:statuses) and
>         queuedTaskHolder.queueId = :queue\n" +
>                 "order by queuedTaskHolder.id
>         asc").setParameter("statuses",
>         ImmutableList.of(TaskStatus.CANCELLED,
>         TaskStatus.COMPLETED)).setParameter("queue", "queue");
>                 return query.getResultList();
>         ============================
>
>
>
>         Thanks,
>
>
>         Le 07/02/2018 à 17:30, Steve Ebersole a écrit :
>>         Yes, I can see this being a problem. Its caused by some very
>>         old, fulgy code in how "list-valued parameters" are handled
>>         internally.
>>
>>         I'm not sure the best way to deal with this. Unfortunately
>>         reverting this is not possible - its necessary for JPA
>>         compliance.  The simple workaround of course is to use named
>>         parameters yourself.  Honestly JPA's notion of "positional"
>>         parameters is nonsensical since they are not positional - the
>>         ordinals can repeat and can appear in any order... nothing
>>         particularly positional about that.  In fact they are really
>>         nothing more than named parameters that happen to use
>>         int-valued labels.
>>
>>         Longer term 6.0 will address this because it changes that
>>         "old, fulgy" internal code - but those same changes are not
>>         possibly in 5.3.
>>
>>
>