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From Andrus Adamchik <and...@objectstyle.org>
Subject Re: Archive tables
Date Fri, 19 Dec 2014 10:23:58 GMT
Yeah, you'd start 2 runtimes, and rename a subset of DbEntities in one of them to add "_A".


Andrus


> On Dec 19, 2014, at 11:51 AM, Markus Reich <markus.reich@markusreich.at> 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 <andrus@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.reich@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 <andrus@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.reich@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
>>>> 
>>>> 
>> 
>> 


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