Data synchronization

[Bart Pietercil]

On 3-sep-07, at 10:26, Ruslan Zasukhin wrote:

> On 3/9/07 10:40 AM, "Alex Shaw" <alex at harryscollar.com> wrote:
>
>> Hi Ruslan
>>
>> In relation to your question, I am interested in .. b) off-line  
>> client
>> to Vserver synch.
>>
>> But..
>>
>> I have a simple & probably very common scenario.
>
> Yes, we want collect the most common needs of Valentina users,
> To implement them in the first turn.
>
>> Small group of multiple users, most users have local network  
>> access and
>> other users on the road with laptops.
>>
>> Laptops are equipped with wireless broadband but will be required  
>> to do
>> offline changes. Changes are synced when network is available.
>> Some of these changes involve structural as well as simple data  
>> changes.
>
> And here main question we have:
>
> Does laptops should have
>     a) the whole snapshoot of server db ?
>     b) or its part?
>     c) or nothing at all?
>
> Case c) means that we need only one direction synch
>             Client => Server
>
> Case a) means bi-direction synch
>             Client <=> Server
>
> Case b) the same as a)  but also require way to specify some  
> FILTERs to load
> from server only some PART of info.
>
>

Very much B (sorry :-)). Even from a data security viewpoint alone  A  
would be unacceptable. There is no way that a database administrator  
would allow to sync a complete database (with maybe confidential  
data) when the outbound person would only need ie. a product catalog.

C is also the same as B when the client loads a filter that returns 0  
records

> ---------------------
>> I know that is asking a lot but I am flexible to the types of offline
>> changes to be allowed. Possibly limiting or removing ability to do
>> structural changes. I am experimenting with different table  
>> structures
>> to allow flexibility.
>>
>> Current single user application is written in Rev & uses sqlite  
>> but have
>> been planning to switch to valentina. Now seriously planning
>> implementation of multi-user requirements.
>>
>> I do have Valentina's Rev ADK but not Vserver.
>
> We have upgrade from ADK to VDN option.
>
>> Maybe embedded Vserver is an option but your wiki is low on  
>> details on
>> what is involved to integrate into main rev application.
>
> Please ask specific questions on Valentina list,
> And I will try give you points to correct WIKI pages.
>
>> I prefer a customised HTTP server approach in which the main server
>> pushes and pulls information from connected client apps. This also
>> allows possibility of using third-party access in the future. eg.
>> limited web-browser access.
>
> Okay I see.
>
> Actually we did develop HTTP access for Valentina server more than  
> year ago.
> But it is not in game yet, because we did plan use it with XML  
> features and
> they are still on hold.


Do you mean here giving SOAP capabilities to Valentina (because  
that's probably in a few months on our plate) ?



>
>> Looking forward to playing with 3.3 but will prefer to wait till  
>> final
>> version is available.
>>
>> regards
>> alex
>
>

Still though we would very much like the features talked about, I  
don't really see how one could implement stable remote syncing  
without having transactions available to the engine.
In my eyes syncing would come after transactions in the roadmap.

Of course what I would like most is you advancing transactions to the  
next build :-)


Bart Pietercil