very interesting, but we are using Oracle, Oracle has Partioning too, but I think this is just all within one table
Andrew Lindesay <a...@lindesay.co.nz> schrieb am Fri Dec 19 2014 at 10:18:12: > Hello Markus; > > An idea that may or may not suit your situation; > > Are you using something like Postgres (PG) [1]? If so, you could create > a 'master' table with 'child' tables -- a concept known as > "partitioning". One might sometimes "partition" data like this based on > something like a natural timestamp of your data such as the > "create_timestamp" or similar, but it ought to be possible to partition > based on a boolean column "archived" for example. This is a simplistic > overview and a guess at what you are trying to do; see [2] for some more > reading. > > If you model the master table in Cayenne and include the column that you > are partitioning on, it should allow you to control if it hits the main > table, the archive table or the archive and main table. Obviously this > would require the qualifiers to be doctored in the application-server to > suit. > > [1] http://www.postgresql.org/ > [2] http://www.postgresql.org/docs/9.3/static/ddl-partitioning.html > > Regards; > > On 19/12/14 9:51 pm, Markus Reich wrote: > > ad 1., yes it's a multiuser web app > > ad 2., it's just a subset, not all tables of the schema have archive > tables > > ad 3., archive tables have a postfix _A in the tablename and are in the > > same schema, but it would be not problem to transfer them to another > scheme > > > > The idea with the two runtimes sounds interesting > > > > > > Andrus Adamchik <and...@objectstyle.org> schrieb am Fri Dec 19 2014 at > > 09:45:08: > > > >> A few more things I need to ask: > >> > >> * I assume it is a multi-user app? > >> * If a user checks the checkbox, you switch *all* entities to the > archive > >> tables, not just a subset of entities? > >> * How do you distinguish between regular and archive tables? Are > archives > >> in a separate schema, or in the same schema, but using different naming > >> conventions? > >> > >> But here is also an idea of the solution, that can be further tweaked > >> depending on the answers. You need to start 2 ServerRuntime's (I assume > you > >> are on Cayenne 3.1 / 4.0 here). One mapped to access regular tables, and > >> another - the archive tables. And depending on a given user state, you > >> allocate them an ObjectContext from the corresponding runtime. > >> > >> Andrus > >> > >> > >>> On Dec 19, 2014, at 11:24 AM, Markus Reich < > markus.re...@markusreich.at> > >> wrote: > >>> > >>> Hi Andrus, > >>> > >>> the switch is durring runtime, so it's not defined at start up. The > >> trigger > >>> is e.g. a checkbox in the ui where the user can decide if he want to > read > >>> from archive. One idea was to create a view over archive and real > table, > >>> because it's only read only necessary. > >>> > >>> > >>> Andrus Adamchik <and...@objectstyle.org> schrieb am Fri Dec 19 2014 at > >>> 08:22:26: > >>> > >>>> I guess the answer depends on what "easily" means. So a few questions > to > >>>> clarify the scenario: > >>>> > >>>> When you start an app, do you already know whether it will read from > >>>> regular or archive tables? If not, what event triggers the switch in > the > >>>> running app? Is this for all sessions or just specific users? > >>>> > >>>> Andrus > >>>> > >>>>> On Dec 19, 2014, at 10:08 AM, Markus Reich < > >> markus.re...@markusreich.at> > >>>> wrote: > >>>>> > >>>>> Hi, > >>>>> > >>>>> I need some hints for a very special issue :-) > >>>>> We have archived old entries of our tables to shadow tables, which > have > >>>>> exactly the same columns structure as the source table. > >>>>> > >>>>> No we need to have a possibility to switch easily between real and > >>>>> shadowtable. > >>>>> Maybe someone already is/was facing such a constellation? > >>>>> > >>>>> thx > >>>>> Meex > >>>> > >>>> > >> > >> > > > > > -- > Andrew Lindesay >
