On Aug 31, 2012 3:02 AM, "Max Rydahl Andersen" <max.ander...@redhat.com> wrote: > > and having > > On 31 Aug 2012, at 01:59, Steve Ebersole <st...@hibernate.org> wrote: > > > Correct. The current proposal has them passed in as settings. > > okey, so I must be missing something - since no access to database metadata how is the autodetection of name/version supposed to work when users have not passed in the settings ?
Two different things: 1) Auto-detection is something we do while building the sessionfactory. 2) JPA defined schema export which Linda wants to have work even when the database is not available (no different from our current SchemaExport really) Auto-detection while building the sessionfactory *will* have access to the dba metadata or building the sessionfactory will fail. Though maybe we also add recognition of these JPA config values, then determining dialect would be: 1) explicit dialect 2) explicit JPA db/version sittings 3) querying the jdbc metadata, if available 4) fail That is actually exactly what we do today except that (2) would be new addition. The argument against adding (2) is that these JPA settings are meant for a very specific purpose > > > Yes, we could "mock" DatabaseMetadata, but there is a lot there including access to the Connection from which the DatabaseMetadata was supposedly retrieved. > > And something like would be too weird: > > public Dialect resolveDialect(String dbname, String version, DatabaseMetaData dbmetadata) > > Where dbmetadata is null if not available ? Well that is an option. Let's see what others think. But I am not a fan of passing in just the single String version. I brought this up to the JPA group too and it looks like this will change there to allow access to (int) major/minor. > > /max > > > On Thu 30 Aug 2012 02:31:56 AM CDT, Emmanuel Bernard wrote: > >> I imagine the DB name + version will be provided by the user somehow. > >> We could also have Hibernate build a DatabaseMetadata implementation returning the data provided by the user. > >> That would avoid changing the contract. The main drawback is that DatabaseMetadata has many more methods > >> we would not be able to honor. > >> > >> On 29 août 2012, at 19:58, Steve Ebersole wrote: > >> > >>> Like I said in the original email, the connection may or may not be > >>> available. Which means we cannot rely on it being available. Nor do > >>> we rely on it being available today either btw. The difference is just > >>> that today in those cases we expect the user to manually name the > >>> dialect to use. > >>> > >>> On Wed 29 Aug 2012 12:26:17 PM CDT, Max Rydahl Andersen wrote: > >>>> hmm - any reason why jpa won't pass in DatabaseMetadata ? > >>>> > >>>> how would one identify name and version anyway if that is not available ? > >>>> > >>>> /max > >>>> > >>>> On 29 Aug 2012, at 16:43, Steve Ebersole <st...@hibernate.org> wrote: > >>>> > >>>>> I think we need to consider changing DialectResolver to fit with some > >>>>> upcoming JPA 2.1 features. > >>>>> > >>>>> JPA 2.1 is adding some form of schema export. The initial plan there is > >>>>> to identify the "dialect" to target by passing in the (1) database name > >>>>> and (2) database version as it would come from JDBC DatabaseMetaData. > >>>>> The connection may or may not be available. > >>>>> > >>>>> Currently we just pass the DatabaseMetaData to the DialectResolver: > >>>>> > >>>>> public Dialect resolveDialect(DatabaseMetaData metaData) > >>>>> > >>>>> The original thinking was to support resolvers looking at information > >>>>> other than just name/version ion making the determination (or even in > >>>>> potentially configuring the Dialect before return). However all our > >>>>> implementations are based on just name/version resolution. > >>>>> > >>>>> Even worse the current proposal proposes using (String) > >>>>> DatabaseMetaData#getDatabaseProductVersion whereas we use (int) > >>>>> DatabaseMetaData#getDatabaseMajorVersion and (int) > >>>>> DatabaseMetaData#getDatabaseMinorVersion inside the standard resolver > >>>>> > >>>>> So should we change this contract? > >>>>> > >>>>> public Dialect resolveDialect(String dbName, int majorVersion, int > >>>>> minorVersion) > >>>>> > >>>>> or > >>>>> > >>>>> public Dialect resolveDialect(String dbName, String dbVersion) > >>>>> > >>>>> WDYT? > >>>>> > >>>>> -- > >>>>> st...@hibernate.org > >>>>> http://hibernate.org > >>>>> _______________________________________________ > >>>>> hibernate-dev mailing list > >>>>> hibernate-dev@lists.jboss.org > >>>>> https://lists.jboss.org/mailman/listinfo/hibernate-dev > >>>> > >>> > >>> -- > >>> st...@hibernate.org > >>> http://hibernate.org > >>> _______________________________________________ > >>> hibernate-dev mailing list > >>> hibernate-dev@lists.jboss.org > >>> https://lists.jboss.org/mailman/listinfo/hibernate-dev > >> > > > > -- > > st...@hibernate.org > > http://hibernate.org > _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
