I was excited to hear that there might already be a technique for
doing this. Thanks for the information on that. Unfortunately I've
run into some trouble. The Mappings information returned by
CreateMappings is missing some things:
1. ReferencedTable on the foreign keys is not set. I worked around
this by calling configuration.GetClassMapping on the
ReferencedEntityName.
2. The many-to-many tables don't have any columns.
As a side note, I also had to call BuildMapping() to get a reference
to the IMapping to pass into GetSqlTypeCode on the column. This seems
like a bit of a heavy approach for getting information that NHibernate
is computing anyways.
Any ideas on dealing with #2? Any insight is much appreciated.
Patrick
On Aug 14, 6:52 am, Fabio Maulo <[email protected]> wrote:
> Yes it is.
>
> This method in Configuration class is available since NH1.2.0 or so
> public Mappings CreateMappings(Dialect.Dialect dialect)
>
> With the Mappings class you can add new object and/or
> public IEnumerable<Table> IterateTables
> public IEnumerable<Mapping.Collection> IterateCollections
> public IDictionary<string, FilterDefinition> FilterDefinitions
>
> With the Table class
> public virtual IEnumerable<Index> IndexIterator
> public IEnumerable<ForeignKey> ForeignKeyIterator
> public virtual IEnumerable<UniqueKey> UniqueKeyIterator
> public virtual PrimaryKey PrimaryKey { get; set; }
> public virtual IEnumerable<Column> ColumnIterator
> public string SqlCreateString(Dialect.Dialect dialect, IMapping p, string
> defaultCatalog, string defaultSchema)
> public string[] SqlAlterStrings(Dialect.Dialect dialect, IMapping p,
> ITableMetadata tableInfo, string defaultCatalog,
> string defaultSchema)
>
> and so on.
>
> Do you need something else ?
>
>
>
> On Fri, Aug 13, 2010 at 11:43 PM, Patrick Earl <[email protected]> wrote:
> > Indeed, it may be unneeded. Maybe I should be posting to the users
> > list instead.
>
> > We use ActiveRecord to initialize the database, and then to access all
> > the table and foreign key information, we use the following code:
>
> > NHibernate.Cfg.Configuration configuration =
> > sessionFactoryHolder.GetAllConfigurations()[0];
> > configuration.SecondPassCompile();
> > Objects = new
> > MetaObjectCollection(configuration.TableMappings,
> > configuration.mapping);
>
> > The MetaObjectCollection constructor then accesses the list of tables
> > from TableMappings and generates its own view of the database schema
> > from that. The mapping is used in a call to
> > Column.GetSqlTypeCode(mapping).
>
> > Basically, we need a mechanism to access what NHibernate thinks the
> > database should look like... all the tables, columns, foreign keys,
> > primary keys, etc.
>
> > Does something like this already exist?
>
> > Patrick Earl
>
> > On Aug 13, 11:18 am, Fabio Maulo <[email protected]> wrote:
> > > Try to explain because, even if there is no problem to make something
> > > public,
> > > to me your patch seems unneeded.
>
> > > On Fri, Aug 13, 2010 at 1:32 PM, Patrick Earl <[email protected]> wrote:
> > > > We have been maintaining an internal patch to NHibernate for quite
> > > > some time, and I'd ultimately like to be able to run on an unpatched
> > > > version of NHibernate. The internal patch we use allows us to access
> > > > the mapping schema that NHibernate generates. This allows us to build
> > > > our own enhanced system for applying schema updates to the database.
> > > > I'd submit a patch, but I'm not really sure in which direction to go.
> > > > I'd love some feedback on how this might be done.
>
> > > > Here's what our internal patch does to Configuration.cs:
>
> > > > - private IMapping mapping;
> > > > + public IMapping mapping;
>
> > > > - private ICollection<Table> TableMappings
> > > > + public ICollection<Table> TableMappings
>
> > > > - private void SecondPassCompile()
> > > > + public void SecondPassCompile()
>
> > > > Looking forward to hearing people's thoughts.
>
> > > > Patrick Earl
>
> > > --
> > > Fabio Maulo
>
> --
> Fabio Maulo
