I also am not sure about this passage in discussing
'javax.persistence.ddl-create-script-target' and
'javax.persistence.ddl-drop-script-target':
<quote>
The persistence provider must produce both create and drop scripts if
the corresponding
DDL targets are specified. This is independent of whether a drop action
is included in the
value passed for the javax.persistence.schema-generation-action property.
</quote>
To me, this sounds like you are saying that the following config will
generate both create and drop scripts:
javax.persistence.schema-generation-action=create
javax.persistence.ddl-create-script-target=<something>
javax.persistence.ddl-drop-script-target=<something>
even though the config explicitly specified just create scripts. Is
that your intent?
Same for:
javax.persistence.schema-generation-action=drop
javax.persistence.ddl-create-script-target=<something>
javax.persistence.ddl-drop-script-target=<something>
that is supposed to generate both create and drop scripts?
Perhaps the reasoning is that javax.persistence.schema-generation-action
is really just geared towards
javax.persistence.schema-generation-action=database. But if that is the
case, maybe we ought to rename the setting to be more explicit of that
fact or at least document it in the discussion of
'javax.persistence.schema-generation-action'
On 01/31/2013 01:13 PM, Steve Ebersole wrote:
> One quick question.
>
> For 'javax.persistence.schema-generation-source' values of
> metadata-then-scripts and scripts-then-metadata is the order the same
> for both create and drop?
>
> I can envision a situation, for example, with metadata-then-scripts
> where the metadata creates a table and then the script creates a
> procedure. I am not sure that all databases will allow you to drop
> the table if other database objects refer to it. Would it be better
> to say that the defined order (x-then-y) applies to create, but the
> reverse order (y-then-x) applies to drop?
>
>
> On 01/31/2013 12:49 PM, Steve Ebersole wrote:
>> These look great. Thanks Linda.
>>
>> On 01/28/2013 05:14 PM, Linda DeMichiel wrote:
>>> There are currently a few open issues in schema generation that need
>>> clarification. These pertain to sections 9.4 ("Schema generation")
>>> and 8.2.1.9 ("properties") in the spec.
>>>
>>> I've made some clarifications and proposed some additions to the
>>> metadata for schema generation as described below. The draft I've
>>> just uploaded reflects these changes
>>> (http://java.net/projects/jpa-spec/downloads/download/JavaPersistence01282013.pdf).
>>> Please review these sections and post any feedback. Changes are
>>> summarized below.
>>>
>>> ----
>>>
>>> Section 9.4
>>>
>>> This section isn't sufficiently clear about requirements for the
>>> specification of schema-generation-action and schema-generation-target.
>>>
>>> I've clarified that schema-generation-action must be specified or no
>>> actions will be taken. This was an assumed default in the current
>>> public draft, but IMO not sufficiently explicit.
>>>
>>> Given the clarification to schema-generation-action, I think it now
>>> makes sense for schema-generation-target to have default values.
>>> That is, if script targets are specified by the properties for scripts,
>>> then generation actions should default into scripts. If not, actions
>>> should be directly into the database.
>>>
>>> The current public draft assumes that if script sources are specified,
>>> generation should occur from scripts exclusively; and conversely, if
>>> script sources are not specified, generation should occur exclusively
>>> from the ORM metadata. I've gotten feedback that this wasn't
>>> sufficiently
>>> flexible, and that we should support a combination of ORM and script
>>> sources. (For example, consider the case where generation should occur
>>> from scripts, but it is desirable to add stored procedures to the
>>> database.)
>>> I therefore propose that we add a schema-generation-source property
>>> that will support such combination. Again, if script sources are
>>> specified
>>> by the properties for scripts, then generation will default to use of
>>> only script sources; if script sources aren't specified, then
>>> generation
>>> will default from the ORM metadata.
>>>
>>> I've also received feedback (from our JPA/EE integration engineer) that
>>> we need to specify that in Java EE environments that strings
>>> corresponding
>>> to file URLs must use absolute (and not relative) paths. I've added
>>> that
>>> clarification as well.
>>>
>>>
>>> Section 8.2.1.9
>>>
>>> In the current public draft, this section lacks information as to how
>>> script locations are specified. I've added a clarification that
>>> scripts packaged as part of the application must be specified relative
>>> to the root of the persistence unit, as we do for other packaged
>>> artifacts. I've also added a clarification about the expectations for
>>> use of file URLs in Java EE environments as above.
>>>
>>> Finally, when I wrote this up initially, I was reluctant to add
>>> metadata for schema generation actions (including targets) because I
>>> believed that such metadata should not be specific to the persistence
>>> unit definition itself. It seems however that people expect that the
>>> use of these properties (as specified in section 9.4) will be
>>> available anyway, whether they are specified in the spec document or
>>> not, and that some vendors will support these anyway as well.
>>> Further, this additional metadata may facilitate ease of use in
>>> prototyping/development environments. I've therefore added these
>>> properties into 8.2.1.9. If you disagree, please speak up.
>>>
>>>
>>> thanks,
>>>
>>> -Linda
>>>
>>>
>>>
>>>
>>
>